HT800 Flame Retardant Silicone Sponge Sheet

HT800 offers the lightness of a sponge combined with the superior sealing capabilities of traditional silicone. This foam is ideal for protecting and sealing outdoor communication, electronics and lighting enclosures. It can also be used for vibration dampening. HT800’s memory and low stress relaxation makes it ideal for gasketing, and its Ozone, UV and extreme temperature resistance make it suitable for use in all environments. 

Its cell structure prevents penetration by particles or water. Applications include, but are not limited to door seals, HVAC systems, lighting housing gaskets, gap fillers, vibration dampening and electrical display gaskets in the rail industry, gaskets, anti-vibration cushioning, HVAC systems, anti-fogging seals, battery pads/cushions and air bag seals in the automotive industry and sound dampening, window panel seals, gap fillers, HVAC systems and thermal insulation in the aerospace industry.

You are buying a minimum of 1 linear metre (915mm wide). Multiple orders will be supplied in a continuous roll.



BISCO HT-800 Medium Cellular Silicone is a versatile, medium firmness silicone. HT-800 silicone foam leads the market in sealing and protecting outdoor communication, electronics and lighting enclosures. HT-800 silicone foam’s superb memory and low stress relaxation reduces maintenance costs from gasket failures caused by compression set and softening. Its compact cell structure and unique formulation provide enhanced sealing against penetration from fine particles and wind-driven rain and fire. It also offers shock reduction and vibration isolation in electronic components and transportation vehicles.


  • Compact cell structure and unique formulation
  • Available in thicknesses from 0.031 to 0.500 in.
  • Typical density of 22 PCF
  • CFD range of 6-14 PSI
  • Resistant to UV, ozone, extreme temperatures and flame


  • FDA compliant
  • Offers consistent performance in all environments
  • Excellent memory and low stress relaxation
  • Reduces maintenance costs associated with gasket failures due to compression set and softening

Additional information


Grey, Black


0.8mm, 1.6mm, 2.4mm, 3.2mm, 4.8mm, 6.4mm, 8.0mm, 9.5mm, 12.7mm