The key is a high percentage fill of recycled, chopped carbon fibre strands which are held in suspension by the foaming action of the sealant within the tire. Upon puncture, the sealant rushes to escape the hole, carrying thousands of carbon filaments which serve to dam up the opening, just like sticks of a beaver dam blocking a stream. This dam of fibre collects more fibre and what was one large hole, is now turned into hundreds of smaller holes for the sealant to seal. Fiberfoam technology has proven to seal up to 7.5mm holes and cuts at gravel pressures and up to 5mm holes at higher road pressures. Even better, the carbon fibre/latex plug formed at the puncture has proven to be more than twice as strong over time as latex only or latex with crystals or glitter. While most sealants claim they can plug holes up to 6+mm, they can also be injected into the tyre through the 3mm hole in your valve stem with some injectors using tips as small as 2mm. The power of carbon fibre makes this impossible, Silca Ultimate Tubeless Sealant will instantly plug your injection syringe or your valve as the fibres stack up to block the opening. In solving this issue, the Silca team has developed Ultimate Tubeless Sealant into a system that will save you time and money in the long run. The initial installation of Silca Ultimate Tubeless Sealant must be done by pouring into the tyre cavity rather than injecting through the valve. However, unlike other sealants which must be completely replaced every 3-6 months, Silca Ultimate Tubeless Sealant has a special Replenisher which can be pumped through the valve and can extend the sealant life to well over 1 year depending on your climate. This means less wasted sealant, and less hassle over time as there is no need to remove the old sealant at each service interval, in many cases, the sealant may outlast the tyre.