One 200mm x 200mm x 25mm High Density Premium Vermiculite Board This 200mm x 200mm x 25mm fire brick slab is suitable for building cooking chambers in wood fired ovens, for creating fireplaces, all sorts of fire boxes and wood heaters The 200mm x 200mm x 25mm heat resistant brick can withstand temperatures up to 1250 degrees and can be used for continuous heating without worry of combustion Due to the smooth, porous surface, the oven brick has exceptional heat resistant capabilities — the 200mm x 200mm x 25mm large brick has low thermal conductivity providing greater energy efficiency With a thickness of approximately 25mm, and high heat retention, the chamotte brick can also be used as a food warming plate or for making small rustic pizzas in any standard oven