One 250mm x 303mm x 30mm High Density Premium Vermiculite Board This 250mm x 303mm x 30mm 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 250mm x 303mm x 30mm 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 250mm x 303mm x 30mm large brick has low thermal conductivity providing greater energy efficiency With a thickness of approximately 30mm, 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