RS-99 is a high density fiber based ceramic material with greater than 99% alumina purity. Type RS-99 has strength equal to asbestos cement and therefore is an excellent replacement for asbestos cement materials. Refractory Sheet Type RS-99 is usable to temperatures of 1650°C (3002°F) and is able to withstand over 500 hours continuous submersion in molten aluminum at 750°C (1382°F) with no wetting and no degradation in properties. Type RS-99’s high alumina content is ideal for high vacuum, reducing atmospheres, and other applications where silica cannot be tolerated. Refractory Sheet RS-99 boards are available in four types:

• Type RS-99M is a plastic highly moldable sheet ideally suited for forming custom geometries.
• Type RS-99W boards can be moistened with water and molded into any desired shape. After low temperature bake-out of 300°C (570°F) boards are unaffected by moisture.
• Type RS-99R boards are prefired and are unaffected by moisture. They stay rigid even if saturated with water.