SIMOND STORECeramic Fiber Insulation Board - 2300F Rated - 1 Inch x 12 Inch x 12 Inch - Ceramic Thermal Insulation Board for Wood Stoves Fireplaces Furnaces Forges Kilns Boilers Pizza Ovens

I had to add an extra piece of insulation board to replacement boards in my fireplace. The initial replacements I bought were too small and reduced the fireplace's efficiency. Rather than buy the correct and costly boards, I was able to buy this single ceramic board at a very affordable price, then cut it with a small tile cutter, to the exact additional measurement. The results (see image) are already evident and at a bargain price.