1/2" Kaowool 2300 °F. Ceramic Fiber Blanket + Insulating FireBrick =Both are 2300F. Kaowool 2300 °F. Kaowool is refractory spun with Alumina and Silica in addition to Kaolin. ( 1 ) K-23 insulating firebrick 9 x 4.5 x 2.5".
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