Service rating to 1000°F / 538°C. Flexible for installation around tight corners and friction fit "U" channels. These tapes are easily bondable with Gaskets Inc adhesive. Fiberglass is a cost effective thermal protection resistant to most chemicals (pH range 4 - 9) with the exception of Hydrofluoric and Hot Phosphoric Acid and wet Hydrogen Chloride. Fiberglass will not burn, smolder or absorb water.