Description

Product Data Sheet

BISCO® HT-840 is an extra-firm silicone foam engineered for demanding applications that require maximum sealing strength and durability. With a denser, more robust structure than softer silicone foam grades, it provides enhanced tear and tensile strength—delivering sealing performance comparable to traditional sponge rubber.

Its compact cell structure allows HT-840 to create tight, reliable seals against dust, moisture, air, and light, making it ideal for protecting outdoor enclosures such as lighting systems, HVAC units, and electronic cabinets. Designed for high closure force applications, it is well-suited for environments where a stronger, more rigid gasket is required.

Manufactured with advanced silicone chemistry and a patented cell structure, HT-840 offers long-term performance with excellent memory and low compression set. This helps maintain sealing integrity over time, reducing maintenance and improving reliability in applications exposed to repeated compression or harsh conditions.

HT-840 performs consistently across a wide temperature range from -55°C to 200°C and resists UV exposure, ozone, and environmental aging. It also meets stringent flame-retardant standards such as UL 94 V-0 and HF-1, making it suitable for applications where fire safety and environmental resistance are critical.

Commonly used in transportation, electronics, industrial equipment, and outdoor enclosures, BISCO® HT-840 provides dependable sealing, cushioning, and vibration isolation. Its combination of firmness, durability, and environmental resistance makes it the ideal choice for high-performance applications requiring long-term reliability under tough conditions.