Silicone sponge is an excellent material for gasketing applications that require a soft compressible material. It is resistant to extreme temperatures and offers good compression set. It is available in Soft, Medium, Firm, and X- Firm Densities. Medium Density is the most popular. It is available in many colors. Generally the surface has a fine fabric finish on both sides and is available in continuous rolls up to 1/2" thick and sheets up to 2" thick.

The given values are typical properties and are provided for information only. They should not be used to set specification requirements. It is up to the end user to determine whether the material is suitable for the intended application.
Unit of Measure


Cell Structure

N/A Closed

Surface Skin

N/A Fine Fabric


N/A Silicone


N/A Closed Cell Sponge


N/A Medium


N/A Red


N/A 36 in

Density Under 1/4" thick

N/A 0.020 lbs/in³

Max. Density Under 1/4" thick

N/A 0.025 lbs/in³

Density Over 1/4" thick

N/A 0.018 lbs/in³

Max. Density Over 1/4" thick

N/A 0.020 lbs/in³

Compression Deflection

N/A 11 psi

Compression Set, 22 hrs @ 212ºF

N/A 29

Max. Compression Set, 22 hrs @ 212ºF

N/A 60 %

Temperature Range

N/A -103 to 450 ºF

UV/ Ozone Resistance

N/A Excellent

Approx. Dielectric Strength

N/A 150 V/mil

Max. Water Absorption

N/A 5 %

Tensile Strength

N/A 100 psi


N/A 200 %

Thermal Conductivity

N/A 0.6 in./hr ft²/ºF

Lead Time

N/A Call or Email Customer Service

Testing Information

Physical Properties

Properties Test Method
Density, lbs/cubic in. Under 1/4" thick ASTMD1056
Density, lbs/cubic in. Over 1/4" thick ASTMD 1056
Compression Deflection, PSI ASTMD575
Compression Set, 22 hrs @ 212 ºF ASTMD 395
Brittle Point ºF ASTM D 746
Temperature Range ºF ASTMD 573
Water Absorption ASTM D 471
Tensile Strength, PSI ASTMD 412
Elongation, % ASTMD 412
Thermal Conductivity BTU in./hr. ft2 ºF ASTM F 433



  • Extreme High & Low Temperatures
  • High Compressibility
  • Low Compression Set
  • UV / Ozone Resistant
  • Excellent Gasketing Material

Additonal Specifications


  • AMS3195
  • MIL-R-46089
  • MIL-R-6130
  • MIL-STD670TE12