Bio Soluble (Calcium Magnesium Silicate) Fibre Kiln Packing: our kiln packing is made of wire reinforced bio soluble packing, with a further external 100% coverage of steel meshes. This overbraiding prevents the packing from fraying and it remains intact for longer in the kiln truck seat. The Bio Soluble layer is rated to 1000°C with the Stainless Steel layer rated to 650°C.