ZRCI Silica-Magnesia Blanket Type RSBL-SOL is made from soluble non-RCF fiber formed into a mechanically needled flexible blanket capable of withstanding continuous operating temperatures up to 1260 C (2300 F). Extra long spun fibers, cross-locked through a forming process, provide a blanket having good handling strength. It is unaffected by most chemicals except hydrofluoric and phosphoric acids and concentrated alkalis. If wetted by water or steam, thermal and physical properties remain unaffected after drying. The blankets provide resistance to attack from molten aluminum alloys at high temperatures.