SSP makes MIL-DTL-25988, Type 2, Class 1 and 2 fluorosilicones. Choose sheets, rolls, extrusions, or ready-to-mold compounds.
MIL-DTL-25988 is a U.S. military specification that supercedes MIL-R-25988. Older prints may reference SAE-MIL-R-25988, AMS-R-25988, AMS-R-25988B, or AMS 25988.
Concerned about traceability? SSP offers a full Certificate of Analysis (COA) for every batch of material that we make.
MIL-DTL-25988 is a U.S. military detail specification that supercedes MIL-R-25988. It divides compliant fluorosilicones into Type 1 materials for O-Rings and Type 2 materials for molded parts, sheets, strips, and extruded shapes. Within each Type, there are two different classes. Class 1 compounds are for general-purpose use, and Class 2 materials are higher-strength elastomers.
SSP makes Type 1, Class 1 and 2 MIL-DTL-25988 fluorosilicones and supplies them as ready-to-mold compounds, continuous rolls, sheet materials, and extrusions. The table below lists our products. All fluorosilicones are peroxide-catalyzed and heat-cured. For traceability, SSP offers a full certificate of analysis (COA) with every batch.
|
SSP Fluorosilicone |
MIL-DTL-25988 Callouts |
Product Specifications |
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|
Product No. |
Type |
Class |
Grade |
Durometer (Shore A) |
Tensile Strength (psi) |
Elongation (%) |
Tear B (ppi/min) |
|
2 |
1 |
40 |
40 |
1500 |
500 |
130 |
|
|
2 |
1 |
50 |
50 |
1300 |
500 |
225 |
|
|
* SSP083 also meets SAE AMS 3326 |
2 |
1 |
60 |
60 |
1000 |
350 |
150 |
|
2 |
1 |
70 |
70 |
1000 |
250 |
128 |
|
|
2 |
1 |
80 |
80 |
800 |
170 |
102 |
|
|
|
2 | 2 | 75 | 75 | 900 | 150 | 150 |
The table below provide additional information about SSP’s Type 2, Class 1 MIL-DTL-25988 fluorosilicones.
SSP083 is a 60-durometer, peroxide-catalyzed, heat-cured fluorosilicone elastomer that meets SAE AMS 3326 and MIL-DTL-25988-(C), Type 2 Class 1 Gr 60 requirements. Find out if this silicone rubber is right for your application.
SSP100 is a 70-durometer, peroxide-catalyzed, heat-cured fluorosilicone elastomer that meets MIL-R-25988B, Type 2, Class 1, Grade 70 requirements. Find out if this silicone rubber is right for your application.
SSP267 is a 40-durometer, peroxide-catalyzed, heat-cured fluorosilicone elastomer that meets MIL-R-25988B, Type 2, Class 1, Grade 40 requirements. Find out if this silicone rubber is right for your application.
SSP338 is a 50-durometer, peroxide-catalyzed, heat-cured fluorosilicone elastomer that meets MIL-R-25988B, Type 2, Class 1, Grade 50 requirements. Find out if this silicone rubber is right for your application.
SSP372 is an 80-durometer, peroxide-catalyzed, heat-cured fluorosilicone elastomer that meets MIL-R-25988B, Type 2, Class 1, Grade 80 requirements. Find out if this silicone rubber is right for your application.
The table below provide additional information about SSP’s Type 2, Class 2 MIL-DTL-25988 fluorosilicones.
SSP082 is a 75-durometer, peroxide-catalyzed, heat-cured fluorosilicone elastomer that meets MIL-R-25988B, Type 2, Class 2, Grade 75 requirements. Find out if this silicone rubber is right for your application.
Each batch of SSP fluorosilicones is fully-certified, and we provide full traceability throughout the supply chain. As the sample COA below shows, SSP’s performs a complete series of tests to demonstrate that a product complies with MIL-R-25988 (MIL-DTL-83528) requirements.
MIL-DTL-25988 is a U.S. military detail (DTL) specification that covers fluorosilicones for aircraft and aviation applications. With their fluorine additions, these silicone elastomers resist petroleum-based fuels and oils, solvents, and harsh chemicals.
MIL-DTL-25988 fluorosilicones also withstand a wide range of temperatures and maintain their tear and tensile strength when immersed in jet fuel. These fuel-resistant materials can withstand repeated flexing without stress cracking and remain flexible and rubbery.
The MIL-DTL-25988 specification divides compliant fluorosilicones into different types, classes, and grades.
Type | Class | Grade |
2 | 2 | 70 |
2 | 1 | 60 |
1 & 2 | 2 | 70 |
2 | 1 | 40 |
2 | 1&2 | 50 |
2 | 1 | 80 |
MIL-DTL-25988C was published in August 2006, and MIL-DTL-25988D was published in 2021. The U.S. Air Force Research Laboratory (AFRL) grandfathered Revision C fluorosilicones until 2022 but then determined that no suppliers could meet the requirements of the newer Revision D specification.
The U.S. Department of Defense (DoD) then adopted a version of an SAE International standard with technical requirements that match MIL-DTL-25988C. The SAE Standard, AMS-R-25988, supersedes MIL-DTL-25988 and meets MIL-DTL-25988C requirements.
See this PDF of an AFRL presentation for more information.
MIL‑DTL‑25988 is a U.S. military detail specification for fluorosilicone elastomers. It supersedes MIL‑R‑25988 and defines performance requirements for fuel‑resistant fluorosilicones used in aerospace and defense applications.
It replaces MIL‑R‑25988, though older drawings may still reference SAE‑MIL‑R‑25988, AMS‑R‑25988, AMS‑R‑25988B, or AMS 25988. These legacy callouts remain common on older aerospace prints.
The specification divides fluorosilicones into:
Type 1: O‑rings
Type 2: Molded parts, sheets, strips, and extruded shapes Each type includes:
Class 1: General‑purpose fluorosilicone
Class 2: Higher‑strength fluorosilicone SSP manufactures Type 2, Class 1 and Class 2 materials.
SSP supplies these materials as:
Ready‑to‑mold compounds
Continuous rolls
Sheet materials
Extrusions All materials are peroxide‑catalyzed and heat‑cured.
These materials are used in:
Aerospace fuel systems
Defense platforms
Hydraulic and solvent‑exposed sealing
High‑performance industrial applications
Fluorosilicone is chosen for its excellent resistance to fuels, oils, and solvents combined with silicone‑like flexibility.
Depending on grade, SSP fluorosilicones offer:
Durometer: 40–80 Shore A
Tensile strength: 800–1500 psi
Elongation: 170–500%
Tear strength: 102–225 ppi/min These values vary by product number (e.g., SSP267, SSP338, SSP083, SSP100, SSP372, SSP082).
Class 1: General‑purpose fluorosilicone
Class 2: Higher‑strength fluorosilicone with improved mechanical durability Both maintain excellent fuel and solvent resistance.
Yes. SSP provides a full Certificate of Analysis (COA) for every batch, supporting aerospace and defense traceability requirements.
Yes. SSP083 meets both MIL‑DTL‑25988 Type 2, Class 1 and SAE AMS 3326 requirements, making it suitable for applications requiring dual compliance.
Fluorosilicone (FVMQ) provides:
Superior resistance to fuels, oils, and solvents
Good high‑temperature performance
Flexibility similar to silicone Standard silicone cannot withstand fuel exposure; fluorosilicone is engineered specifically for these environments.