FIND OUT MORE ABOUT THE BENEFITS OUR PRODUCTS OFFER.
In addition to fastening, our self-sealing screws and bolts offer a reliable and reusable seal, preventing (or containing!) contamination from dust, air, water, lubricants and other liquid or gaseous substances.
At APM Hexseal, we understand the need for reliable fasteners that can handle extreme conditions where moisture, dust, lubricants, and other factors may compromise the integrity of the hardware or the seal. Our self-sealing screws and self-sealing bolts address these concerns by creating a self-sealing fastener that will hold up to even the harshest environments.
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Fasteners often require additional sealing hardware to prevent leaks and ensure reliable, secure holds. APM Hexseal’s patented Seelskrews® and Seelbolts® combine dependable fastening hardware with weatherproof sealing materials. As a result, our self-sealing screws and bolts offer a reliable and reusable seal, preventing or containing contamination from dust, air, water, lubricants and other liquid or gaseous substances.
They are also vibration-resistant, making them a great choice for applications that encounter day-to-day jarring, or repetitive movement. Should you need a more serious level of vibration-resistance, our screws and bolts are available with additional locking features, such as self-locking pellets, strips, and patches.
Seelskrews and Seelbolts are available in many standard thread sizes and with various O-ring elastomer options. Some additional customizations include specialty thread-forming variations, tamper-resistant drives, thread captivation, and paint and finish options.
For information on maximum torque values for Seelskrews and Seelbolts, please see our table of Torque Values for Self-Sealing Hardware.
Anatomy of Seelskrews and Seelbolts
The anatomy of our Seelskrews and Seelbolts is simple, yet functional. We started the design with a stainless steel screw with an undercut head. The stainless steel provides a strong, corrosion-resistant base that’s ideal for fastening. A silicone O-ring is embedded in the groove under the screw’s head, creating a durable seal that resists moisture and corrosive chemicals.
Once fastened into the clearance hole, a Seelskrew or Seelbolt will offer 360° metal-on-metal contact when fully compressed. The Seelskrew or Seelbolt not only holds the component parts in place, but also helps to seal against intrusion from unwanted fluid, gas, and debris.
Features
APM Hexseal’s Seelskrews and Seelbolts offer a variety of unique features not shared by traditional fastening and sealing hardware, including:
- Positive seals while under pressure or vacuum conditions
- Easy installation
- Removeable and reusable
- Compatibility with all surface finishes
- Broad operating temperature range from -160°F to 500°F (-106°C to 260°C)
- Full 360° metal-to-metal contact for fastening integrity
- Uniform high-strength designs
- UL- and CSA-recognized
- Made in the USA
Installation
Easy installation is one of the best things about our patented Seelskrews and Seelbolts. Simply screw the hardware into the pre-drilled mounting hole using your standard hand or power tools, the same way you would with a regular bolt or screw. As with standard fasteners, it is important to accurately measure your mounting hole and use the appropriately sized Seelbolt or Seelskrew for your application. When using a tool for installation, be sure to let your APM Hexseal representative know so they can offer advice about the best amount of torque for your material and fastener design.
Materials
At APM Hexseal, we understand that every project is different. That’s why we offer our products with a wide range of O-ring elastomer materials, coatings, finishes, and locking designs. O-ring materials we offer include silicone, fluorosilicone, Viton, nitrile, neoprene, and EPDM. Our quality stainless steel screws and bolts are passivated and can be painted or coated to meet the particular requirements of nearly any application. Our representatives will discuss the needs of your project in detail and help you customize the ideal fastener design for your needs.
Applications
APM Hexseal is dedicated to providing customers with functional fixture and sealing solutions for numerous industries and applications. Though ideal for underwater and outdoor applications with exposure to the elements, our Seelskrews and Seelbolts can be customized for many application types. Industries that benefit from our Seelskrews and Seelbolts include:
- Underwater and nautical equipment
- Surface marine vehicles and equipment
- Sensitive instrumentation
- Medical equipment and devices
- Military ground equipment
- Off-road construction equipment
- Aviation and aerospace components
- Automotive components
- Robotics
- Electric, pneumatic, and hydraulic control systems
- Industrial fasteners for infrastructure
- Information and communication structures, cellular towers, and solar panels
About APM Hexseal
With more than 70 years in the fastening industry, APM Hexseal has the experience necessary to develop innovative and functional fastening and sealing solutions for customers in nearly any industry. We pride ourselves on providing only the highest-quality products, backed by numerous certifications.
To learn more about our superior fastening solutions, Ask the Experts at APM Hexseal today!
Ever Better.
- IMPERIAL PAN HEAD with CROSS RECESS DRIVE (PHILLIPS)
- METRIC PAN HEAD with CROSS RECESS DRIVE (PHILLIPS)
- IMPERIAL PAN HEAD with SLOTTED DRIVE
- METRIC PAN HEAD with SLOTTED DRIVE
- IMPERIAL FLAT HEAD with CROSS RECESS DRIVE (PHILLIPS)
- IMPERIAL HEXAGONAL HEAD BOLT
- METRIC HEXAGONAL HEAD BOLT
IMPERIAL PAN HEAD with CROSS RECESS DRIVE (PHILLIPS)
MATERIAL SPECIFICATIONS
For APM Hexseal® Standard Seelskrews® & Seelbolts®
- Screw Material:
- 18/8 Stainless Steel, passivated
- Threads:
- Imperial— Class 2A †; Metric— Class 6g
- O-Ring Elastomer:
- Silicone conforms to A-A-59588, Class 2, GR60 or GR70, Red ‡
- Temperature Range:
- -80° F to +425° F ( -62° C to +219° C)
- Pressure Range:
- Up to 20,000 psig internal and external (subject to clearance hole dimensions).
- Resistant to:
- Splash, salt spray, sunlight, ozone, weather, fungus, dust, and most acids and lubricating oils.
† Standard for stock screws and bolts. ‡ Alternative o-ring elastomers are available. Consult our O-Ring Elastomer Options table for details.
| Thread Size | Drive Size | Min. Length
Available (L) |
Max. Head
Diameter (C) |
Max. Head
Height (D) |
Recommended Clearance
Hole (Min. - Max.) |
|---|---|---|---|---|---|
| 2-56 UNC-2A | #1 | 1/4" | 0.181" | 0.062" | 0.091" - 0.950" |
| 4-40 UNC-2A | #1 | 1/4" | 0.238" | 0.080" | 0.125" - 0.129" |
| 6-32 UNC-2A | #2 | 1/4" | 0.294" | 0.097" | 0.147" - 0.152" |
| 8-32 UNC-2A | #2 | 1/4" | 0.347" | 0.115" | 0.173" - 0.179" |
| 10-32 UNF-2A | #2 | 3/8" | 0.403" | 0.133" | 0.199" - 0.204" |
| 10-24 UNC-2A | #2 | 3/8" | 0.403" | 0.133" | 0.199" - 0.204" |
| 1/4-20 UNC-2A | #3 | 3/8" | 0.517" | 0.175" | 0.265" - 0.269" |
| 1/4-28 UNF-2A | #3 | 3/8" | 0.517" | 0.175" | 0.265" - 0.269" |
For a full list of part numbers, please contact APM Hexseal.
METRIC PAN HEAD with CROSS RECESS DRIVE (PHILLIPS)
MATERIAL SPECIFICATIONS
For APM Hexseal® Standard Seelskrews® & Seelbolts®
- Screw Material:
- 18/8 Stainless Steel, passivated
- Threads:
- Imperial— Class 2A †; Metric— Class 6g
- O-Ring Elastomer:
- Silicone conforms to A-A-59588, Class 2, GR60 or GR70, Red ‡
- Temperature Range:
- -80° F to +425° F ( -62° C to +219° C)
- Pressure Range:
- Up to 20,000 psig internal and external (subject to clearance hole dimensions).
- Resistant to:
- Splash, salt spray, sunlight, ozone, weather, fungus, dust, and most acids and lubricating oils.
‡ Alternative o-ring elastomers are available. Consult our O-Ring Elastomer Options table for details.
| Thread Size | Drive Size | Min. Length
Available (L) |
Max. Head
Diameter (C) |
Max. Head
Height (D) |
Recommended Clearance
Hole (Min. - Max.) |
|---|---|---|---|---|---|
| M2 X 0.40 6g | #1 | 4mm | 4.24mm | 1.60mm | 2.31mm - 2.41mm |
| M2.5 X 0.45 6g | #1 | 4mm | 5.46mm | 2.10mm | 2.67mm - 2.84mm |
| M3 X 0.50 6g | #2 | 4mm | 6.70mm | 2.40mm | 3.55mm - 3.65mm |
| M4 X 0.70 6g | #2 | 4mm | 8.69mm | 3.05mm | 4.39mm - 4.54mm |
| M5 X 0.80 6g | #2 | 6mm | 9.90mm | 3.70mm | 5.56mm - 5.66mm |
| M6 X 1 6g | #3 | 6mm | 12.58mm | 4.60mm | 6.73mm - 6.83mm |
For a full list of part numbers, please contact APM Hexseal.
IMPERIAL PAN HEAD with SLOTTED DRIVE
MATERIAL SPECIFICATIONS
For APM Hexseal® Standard Seelskrews® & Seelbolts®
- Screw Material:
- 18/8 Stainless Steel, passivated
- Threads:
- Imperial— Class 2A †; Metric— Class 6g
- O-Ring Elastomer:
- Silicone conforms to A-A-59588, Class 2, GR60 or GR70, Red ‡
- Temperature Range:
- -80° F to +425° F ( -62° C to +219° C)
- Pressure Range:
- Up to 20,000 psig internal and external (subject to clearance hole dimensions).
- Resistant to:
- Splash, salt spray, sunlight, ozone, weather, fungus, dust, and most acids and lubricating oils.
‡ Alternative o-ring elastomers are available. Consult our O-Ring Elastomer Options table for details.
| Thread Size | Min. Length
Available (L) |
Max. Head
Diameter (C) |
Max. Head
Height (D) |
Recommended Clearance
Hole (Min. - Max.) |
|---|---|---|---|---|
| 2-56 UNC-2A | 1/4" | 0.168" | 0.055" | 0.091" - 0.950" |
| 4-40 UNC-2A | 1/4" | 0.220" | 0.069" | 0.125" - 0.129" |
| 6-32 UNC-2A | 1/4" | 0.271" | 0.083" | 0.147" - 0.149" |
| 8-32 UNC-2A | 1/4" | 0.323" | 0.097" | 0.173" - 0.177" |
| 10-32 UNF-2A | 1/4" | 0.374" | 0.113" | 0.199" - 0.201" |
| 10-24 UNC-2A | 1/4" | 0.374" | 0.113" | 0.199" - 0.201" |
| 1/4-20 UNC-2A | 5/16" | 0.493" | 0.148" | 0.265" - 0.269" |
| 1/4-28 UNF-2A | 5/16" | 0.493" | 0.148" | 0.265" - 0.269" |
For a full list of part numbers, please contact APM Hexseal.
METRIC PAN HEAD with SLOTTED DRIVE
MATERIAL SPECIFICATIONS
For APM Hexseal® Standard Seelskrews® & Seelbolts®
- Screw Material:
- 18/8 Stainless Steel, passivated
- Threads:
- Imperial— Class 2A †; Metric— Class 6g
- O-Ring Elastomer:
- Silicone conforms to A-A-59588, Class 2, GR60 or GR70, Red ‡
- Temperature Range:
- -80° F to +425° F ( -62° C to +219° C)
- Pressure Range:
- Up to 20,000 psig internal and external (subject to clearance hole dimensions).
- Resistant to:
- Splash, salt spray, sunlight, ozone, weather, fungus, dust, and most acids and lubricating oils.
‡ Alternative o-ring elastomers are available. Consult our O-Ring Elastomer Options table for details.
| Thread Size | Min. Length
Available (L) |
Max. Head
Diameter (C) |
Max. Head
Height (D) |
Recommended Clearance
Hole (Min. - Max.) |
|---|---|---|---|---|
| M2 x 0.40 6g | 4mm | 4.24mm | 1.37mm | 2.31mm - 2.41mm |
| M2.5 x 0.45 6g | 4mm | 5.56mm | 1.73mm | 2.67mm - 2.84mm |
| M3 x 0.50 6g | 4mm | 6.22mm | 1.90mm | 3.55mm - 3.65mm |
| M4 x 0.70 6g | 4mm | 8.17mm | 2.43mm | 4.39mm - 4.54mm |
| M5 x 0.80 6g | 6mm | 9.70mm | 3.05mm | 5.56mm - 5.66mm |
| M6 x 1 6g | 6mm | 12.49mm | 3.73mm | 6.73mm - 6.83mm |
| M8 x 1.25 6g | 6mm | 15.62mm | 4.52mm | 8.45mm - 8.55mm |
For a full list of part numbers, please contact APM Hexseal.
IMPERIAL FLAT HEAD with CROSS RECESS DRIVE (PHILLIPS)
MATERIAL SPECIFICATIONS
For APM Hexseal® Standard Seelskrews® & Seelbolts®
- Screw Material:
- 18/8 Stainless Steel, passivated
- Threads:
- Imperial— Class 2A †; Metric— Class 6g
- O-Ring Elastomer:
- Silicone conforms to A-A-59588, Class 2, GR60 or GR70, Red ‡
- Temperature Range:
- -80° F to +425° F ( -62° C to +219° C)
- Pressure Range:
- Up to 20,000 psig internal and external (subject to clearance hole dimensions).
- Resistant to:
- Splash, salt spray, sunlight, ozone, weather, fungus, dust, and most acids and lubricating oils.
‡ Alternative o-ring elastomers are available. Consult our O-Ring Elastomer Options table for details.
| Thread Size | Drive Size | Min. Length Available (L) | Max. Head Diameter (C) | Recommended Clearance Hole (Min. - Max.) |
|---|---|---|---|---|
| 2-56 UNC-2A | #1 | 1/4" | 0.172" | 0.091" - 0.950" |
| 4-40 UNC-2A | #1 | 1/4" | 0.225" | 0.125" - 0.129" |
| 6-32 UNC-2A | #2 | 1/4" | 0.279" | 0.147" - 0.152" |
| 8-32 UNC-2A | #2 | 1/4" | 0.332" | 0.173" - 0.179" |
| 10-24 UNC-2A | #2 | 5/16" | 0.385" | 0.199" - 0.204" |
| 10-32 UNF-2A | #2 | 5/16" | 0.385" | 0.199" - 0.204" |
| 1/4-20 UNC-2A | #3 | 3/8" | 0.507" | 0.265" - 0.269" |
For a full list of part numbers, please contact APM Hexseal.
IMPERIAL HEXAGONAL HEAD BOLT
MATERIAL SPECIFICATIONS
For APM Hexseal® Standard Seelskrews® & Seelbolts®
- Bolt Material:
- 18/8 Stainless Steel, passivated
- Threads:
- Imperial— Class 2A †; Metric— Class 6g
- O-Ring Elastomer:
- Silicone conforms to A-A-59588, Class 2, GR60 or GR70, Red ‡
- Temperature Range:
- -80° F to +425° F ( -62° C to +219° C)
- Pressure Range:
- Up to 20,000 psig internal and external (subject to clearance hole dimensions).
- Resistant to:
- Splash, salt spray, sunlight, ozone, weather, fungus, dust, and most acids and lubricating oils.
‡ Alternative o-ring elastomers are available. Consult our O-Ring Elastomer Options table for details.
| Thread Size | Min. Length Available (L) | Distance Between Flats (C) | Distance Between Points (P) † | Max. Head Height (D) | Recommended Clearance Hole (Min. - Max.) |
|---|---|---|---|---|---|
| 1/4-28 UNF-2A | 3/8" | 0.440" | 0.510" | 0.163" | 0.265" - 0.269" |
| 1/4-20 UNC-2A | 3/8" | 0.440" | 0.510" | 0.163" | 0.265" - 0.269" |
| 5/16-24 UNF-2A | 1/2" | 0.502" | 0.580" | 0.211" | 0.332" - 0.336" |
| 5/16-18 UNC-2A | 3/8" | 0.502" | 0.580" | 0.211" | 0.332" - 0.336" |
| 3/8-24 UNF-2A | 5/8" | 0.565" | 0.650" | 0.243" | 0.395" - 0.399" |
| 3/8-16 UNC-2A | 1/2" | 0.565" | 0.650" | 0.243" | 0.395" - 0.399" |
| 1/2-20 UNF-2A | 1/2" | 0.752" | 0.870" | 0.323" | 0.530" - 0.534" |
| 1/2-13 UNC-2A | 3/4" | 0.752" | 0.870" | 0.323" | 0.530" - 0.534" |
† The values provided for Distance Between Points are for reference only. |
|||||
For a full list of part numbers, please contact APM Hexseal.
METRIC HEXAGONAL HEAD BOLT
MATERIAL SPECIFICATIONS
For APM Hexseal® Standard Seelskrews® & Seelbolts®
- Bolt Material:
- 18/8 Stainless Steel, passivated
- Threads:
- Imperial— Class 2A †; Metric— Class 6g
- O-Ring Elastomer:
- Silicone conforms to A-A-59588, Class 2, GR60 or GR70, Red ‡
- Temperature Range:
- -80° F to +425° F ( -62° C to +219° C)
- Pressure Range:
- Up to 20,000 psig internal and external (subject to clearance hole dimensions).
- Resistant to:
- Splash, salt spray, sunlight, ozone, weather, fungus, dust, and most acids and lubricating oils.
‡ Alternative o-ring elastomers are available. Consult our O-Ring Elastomer Options table for details.
| Thread Size | Min. Length Available (L) | Distance Between Flats (C) | Distance Between Points (P) † | Max. Head Height (D) | Recommended Clearance Hole (Min. - Max.) |
|---|---|---|---|---|---|
| M6 X 1 6g | 8mm | 10mm | 11.28mm | 4.15mm | 6.73mm - 6.83mm |
| M8 X 1.25 6g | 12mm | 13mm | 14.69mm | 5.65mm | 8.45mm - 8.55mm |
| M10 X 1.5 6g | 12mm | 17mm | 19.25mm | 7.18mm | 10.53mm - 10.64mm |
| M12 X 1.75 6g | 20mm | 19mm | 21.50mm | 8.18mm | 12.79mm - 12.9mm |
† The values provided for Distance Between Points are for reference only. |
|||||
For a full list of part numbers, please contact APM Hexseal.
IMPERIAL PAN HEAD with CROSS RECESS DRIVE (PHILLIPS)
MATERIAL SPECIFICATIONS
For APM Hexseal® Standard Seelskrews® & Seelbolts®
- Screw Material:
- 18/8 Stainless Steel, passivated
- Threads:
- Imperial— Class 2A †; Metric— Class 6g
- O-Ring Elastomer:
- Silicone conforms to A-A-59588, Class 2, GR60 or GR70, Red ‡
- Temperature Range:
- -80° F to +425° F ( -62° C to +219° C)
- Pressure Range:
- Up to 20,000 psig internal and external (subject to clearance hole dimensions).
- Resistant to:
- Splash, salt spray, sunlight, ozone, weather, fungus, dust, and most acids and lubricating oils.
† Standard for stock screws and bolts. ‡ Alternative o-ring elastomers are available. Consult our O-Ring Elastomer Options table for details.
| Thread Size | Drive Size | Min. Length
Available (L) |
Max. Head
Diameter (C) |
Max. Head
Height (D) |
Recommended Clearance
Hole (Min. - Max.) |
|---|---|---|---|---|---|
| 2-56 UNC-2A | #1 | 1/4" | 0.181" | 0.062" | 0.091" - 0.950" |
| 4-40 UNC-2A | #1 | 1/4" | 0.238" | 0.080" | 0.125" - 0.129" |
| 6-32 UNC-2A | #2 | 1/4" | 0.294" | 0.097" | 0.147" - 0.152" |
| 8-32 UNC-2A | #2 | 1/4" | 0.347" | 0.115" | 0.173" - 0.179" |
| 10-32 UNF-2A | #2 | 3/8" | 0.403" | 0.133" | 0.199" - 0.204" |
| 10-24 UNC-2A | #2 | 3/8" | 0.403" | 0.133" | 0.199" - 0.204" |
| 1/4-20 UNC-2A | #3 | 3/8" | 0.517" | 0.175" | 0.265" - 0.269" |
| 1/4-28 UNF-2A | #3 | 3/8" | 0.517" | 0.175" | 0.265" - 0.269" |
For a full list of part numbers, please contact APM Hexseal.
METRIC PAN HEAD with CROSS RECESS DRIVE (PHILLIPS)
MATERIAL SPECIFICATIONS
For APM Hexseal® Standard Seelskrews® & Seelbolts®
- Screw Material:
- 18/8 Stainless Steel, passivated
- Threads:
- Imperial— Class 2A †; Metric— Class 6g
- O-Ring Elastomer:
- Silicone conforms to A-A-59588, Class 2, GR60 or GR70, Red ‡
- Temperature Range:
- -80° F to +425° F ( -62° C to +219° C)
- Pressure Range:
- Up to 20,000 psig internal and external (subject to clearance hole dimensions).
- Resistant to:
- Splash, salt spray, sunlight, ozone, weather, fungus, dust, and most acids and lubricating oils.
‡ Alternative o-ring elastomers are available. Consult our O-Ring Elastomer Options table for details.
| Thread Size | Drive Size | Min. Length
Available (L) |
Max. Head
Diameter (C) |
Max. Head
Height (D) |
Recommended Clearance
Hole (Min. - Max.) |
|---|---|---|---|---|---|
| M2 X 0.40 6g | #1 | 4mm | 4.24mm | 1.60mm | 2.31mm - 2.41mm |
| M2.5 X 0.45 6g | #1 | 4mm | 5.46mm | 2.10mm | 2.67mm - 2.84mm |
| M3 X 0.50 6g | #2 | 4mm | 6.70mm | 2.40mm | 3.55mm - 3.65mm |
| M4 X 0.70 6g | #2 | 4mm | 8.69mm | 3.05mm | 4.39mm - 4.54mm |
| M5 X 0.80 6g | #2 | 6mm | 9.90mm | 3.70mm | 5.56mm - 5.66mm |
| M6 X 1 6g | #3 | 6mm | 12.58mm | 4.60mm | 6.73mm - 6.83mm |
For a full list of part numbers, please contact APM Hexseal.
IMPERIAL PAN HEAD with SLOTTED DRIVE
MATERIAL SPECIFICATIONS
For APM Hexseal® Standard Seelskrews® & Seelbolts®
- Screw Material:
- 18/8 Stainless Steel, passivated
- Threads:
- Imperial— Class 2A †; Metric— Class 6g
- O-Ring Elastomer:
- Silicone conforms to A-A-59588, Class 2, GR60 or GR70, Red ‡
- Temperature Range:
- -80° F to +425° F ( -62° C to +219° C)
- Pressure Range:
- Up to 20,000 psig internal and external (subject to clearance hole dimensions).
- Resistant to:
- Splash, salt spray, sunlight, ozone, weather, fungus, dust, and most acids and lubricating oils.
‡ Alternative o-ring elastomers are available. Consult our O-Ring Elastomer Options table for details.
| Thread Size | Min. Length
Available (L) |
Max. Head
Diameter (C) |
Max. Head
Height (D) |
Recommended Clearance
Hole (Min. - Max.) |
|---|---|---|---|---|
| 2-56 UNC-2A | 1/4" | 0.168" | 0.055" | 0.091" - 0.950" |
| 4-40 UNC-2A | 1/4" | 0.220" | 0.069" | 0.125" - 0.129" |
| 6-32 UNC-2A | 1/4" | 0.271" | 0.083" | 0.147" - 0.149" |
| 8-32 UNC-2A | 1/4" | 0.323" | 0.097" | 0.173" - 0.177" |
| 10-32 UNF-2A | 1/4" | 0.374" | 0.113" | 0.199" - 0.201" |
| 10-24 UNC-2A | 1/4" | 0.374" | 0.113" | 0.199" - 0.201" |
| 1/4-20 UNC-2A | 5/16" | 0.493" | 0.148" | 0.265" - 0.269" |
| 1/4-28 UNF-2A | 5/16" | 0.493" | 0.148" | 0.265" - 0.269" |
For a full list of part numbers, please contact APM Hexseal.
METRIC PAN HEAD with SLOTTED DRIVE
MATERIAL SPECIFICATIONS
For APM Hexseal® Standard Seelskrews® & Seelbolts®
- Screw Material:
- 18/8 Stainless Steel, passivated
- Threads:
- Imperial— Class 2A †; Metric— Class 6g
- O-Ring Elastomer:
- Silicone conforms to A-A-59588, Class 2, GR60 or GR70, Red ‡
- Temperature Range:
- -80° F to +425° F ( -62° C to +219° C)
- Pressure Range:
- Up to 20,000 psig internal and external (subject to clearance hole dimensions).
- Resistant to:
- Splash, salt spray, sunlight, ozone, weather, fungus, dust, and most acids and lubricating oils.
‡ Alternative o-ring elastomers are available. Consult our O-Ring Elastomer Options table for details.
| Thread Size | Min. Length
Available (L) |
Max. Head
Diameter (C) |
Max. Head
Height (D) |
Recommended Clearance
Hole (Min. - Max.) |
|---|---|---|---|---|
| M2 x 0.40 6g | 4mm | 4.24mm | 1.37mm | 2.31mm - 2.41mm |
| M2.5 x 0.45 6g | 4mm | 5.56mm | 1.73mm | 2.67mm - 2.84mm |
| M3 x 0.50 6g | 4mm | 6.22mm | 1.90mm | 3.55mm - 3.65mm |
| M4 x 0.70 6g | 4mm | 8.17mm | 2.43mm | 4.39mm - 4.54mm |
| M5 x 0.80 6g | 6mm | 9.70mm | 3.05mm | 5.56mm - 5.66mm |
| M6 x 1 6g | 6mm | 12.49mm | 3.73mm | 6.73mm - 6.83mm |
| M8 x 1.25 6g | 6mm | 15.62mm | 4.52mm | 8.45mm - 8.55mm |
For a full list of part numbers, please contact APM Hexseal.
IMPERIAL FLAT HEAD with CROSS RECESS DRIVE (PHILLIPS)
MATERIAL SPECIFICATIONS
For APM Hexseal® Standard Seelskrews® & Seelbolts®
- Screw Material:
- 18/8 Stainless Steel, passivated
- Threads:
- Imperial— Class 2A †; Metric— Class 6g
- O-Ring Elastomer:
- Silicone conforms to A-A-59588, Class 2, GR60 or GR70, Red ‡
- Temperature Range:
- -80° F to +425° F ( -62° C to +219° C)
- Pressure Range:
- Up to 20,000 psig internal and external (subject to clearance hole dimensions).
- Resistant to:
- Splash, salt spray, sunlight, ozone, weather, fungus, dust, and most acids and lubricating oils.
‡ Alternative o-ring elastomers are available. Consult our O-Ring Elastomer Options table for details.
| Thread Size | Drive Size | Min. Length Available (L) | Max. Head Diameter (C) | Recommended Clearance Hole (Min. - Max.) |
|---|---|---|---|---|
| 2-56 UNC-2A | #1 | 1/4" | 0.172" | 0.091" - 0.950" |
| 4-40 UNC-2A | #1 | 1/4" | 0.225" | 0.125" - 0.129" |
| 6-32 UNC-2A | #2 | 1/4" | 0.279" | 0.147" - 0.152" |
| 8-32 UNC-2A | #2 | 1/4" | 0.332" | 0.173" - 0.179" |
| 10-24 UNC-2A | #2 | 5/16" | 0.385" | 0.199" - 0.204" |
| 10-32 UNF-2A | #2 | 5/16" | 0.385" | 0.199" - 0.204" |
| 1/4-20 UNC-2A | #3 | 3/8" | 0.507" | 0.265" - 0.269" |
For a full list of part numbers, please contact APM Hexseal.
IMPERIAL HEXAGONAL HEAD BOLT
MATERIAL SPECIFICATIONS
For APM Hexseal® Standard Seelskrews® & Seelbolts®
- Bolt Material:
- 18/8 Stainless Steel, passivated
- Threads:
- Imperial— Class 2A †; Metric— Class 6g
- O-Ring Elastomer:
- Silicone conforms to A-A-59588, Class 2, GR60 or GR70, Red ‡
- Temperature Range:
- -80° F to +425° F ( -62° C to +219° C)
- Pressure Range:
- Up to 20,000 psig internal and external (subject to clearance hole dimensions).
- Resistant to:
- Splash, salt spray, sunlight, ozone, weather, fungus, dust, and most acids and lubricating oils.
‡ Alternative o-ring elastomers are available. Consult our O-Ring Elastomer Options table for details.
| Thread Size | Min. Length Available (L) | Distance Between Flats (C) | Distance Between Points (P) † | Max. Head Height (D) | Recommended Clearance Hole (Min. - Max.) |
|---|---|---|---|---|---|
| 1/4-28 UNF-2A | 3/8" | 0.440" | 0.510" | 0.163" | 0.265" - 0.269" |
| 1/4-20 UNC-2A | 3/8" | 0.440" | 0.510" | 0.163" | 0.265" - 0.269" |
| 5/16-24 UNF-2A | 1/2" | 0.502" | 0.580" | 0.211" | 0.332" - 0.336" |
| 5/16-18 UNC-2A | 3/8" | 0.502" | 0.580" | 0.211" | 0.332" - 0.336" |
| 3/8-24 UNF-2A | 5/8" | 0.565" | 0.650" | 0.243" | 0.395" - 0.399" |
| 3/8-16 UNC-2A | 1/2" | 0.565" | 0.650" | 0.243" | 0.395" - 0.399" |
| 1/2-20 UNF-2A | 1/2" | 0.752" | 0.870" | 0.323" | 0.530" - 0.534" |
| 1/2-13 UNC-2A | 3/4" | 0.752" | 0.870" | 0.323" | 0.530" - 0.534" |
† The values provided for Distance Between Points are for reference only. |
|||||
For a full list of part numbers, please contact APM Hexseal.
METRIC HEXAGONAL HEAD BOLT
MATERIAL SPECIFICATIONS
For APM Hexseal® Standard Seelskrews® & Seelbolts®
- Bolt Material:
- 18/8 Stainless Steel, passivated
- Threads:
- Imperial— Class 2A †; Metric— Class 6g
- O-Ring Elastomer:
- Silicone conforms to A-A-59588, Class 2, GR60 or GR70, Red ‡
- Temperature Range:
- -80° F to +425° F ( -62° C to +219° C)
- Pressure Range:
- Up to 20,000 psig internal and external (subject to clearance hole dimensions).
- Resistant to:
- Splash, salt spray, sunlight, ozone, weather, fungus, dust, and most acids and lubricating oils.
‡ Alternative o-ring elastomers are available. Consult our O-Ring Elastomer Options table for details.
| Thread Size | Min. Length Available (L) | Distance Between Flats (C) | Distance Between Points (P) † | Max. Head Height (D) | Recommended Clearance Hole (Min. - Max.) |
|---|---|---|---|---|---|
| M6 X 1 6g | 8mm | 10mm | 11.28mm | 4.15mm | 6.73mm - 6.83mm |
| M8 X 1.25 6g | 12mm | 13mm | 14.69mm | 5.65mm | 8.45mm - 8.55mm |
| M10 X 1.5 6g | 12mm | 17mm | 19.25mm | 7.18mm | 10.53mm - 10.64mm |
| M12 X 1.75 6g | 20mm | 19mm | 21.50mm | 8.18mm | 12.79mm - 12.9mm |
† The values provided for Distance Between Points are for reference only. |
|||||
For a full list of part numbers, please contact APM Hexseal.
