For high-temperature construction projects that require rigid insulation, consider FiberFrax 2300 Duraboard LD boards are ideal as an insulating back-up to firebrick and castable products in flues, chimney linings, furnaces, kilns and ovens. After installation, these boards offer high efficient insulating capability that helps save energy costs and cycling times. The LD boards are manufactured to tighter dimensional tolerances and have an excellent finished surface. These characteristics make it ideally suited for use as a sandwich or core material or for use in the manufacture of components where aesthetic quality, as well as uniformity and performance, is important. They have a 2300 F degree temperature rating.  Minimum three boards to an order. 

You can find the Technical Data Sheet Here.  

Easy-to-cut, these boards are readily available in a 1" x 24" x 48" and 1/2" x 24" x 48" sizes. We sell three boards at a time so you can order in multiples of threes. If you need another size at 716-442-3004. Product data sheets are available on request. Always follow manufacturer's instructions. Wear goggles, gloves and a mask.  Shipping is FREE (contiguous US only).