Bio Soluble (Calcium Magnesium Silicate) Fibre Packing (Stainless Steel Overbraid): manufactured from special bio soluble (body soluble) yarns, they are developed as a direct replacement for harmful asbestos and ceramic products. The bio soluble fibre insulation is rated to 1000°C in situ. The open overbraid of stainless steel enhances the abrasion resistance and prolong the life of the seal considerably.