Universal reversible back brick fit most grates. This fire brick reduces the consumption of fossil fuels, very durable, by lining the inside of the firebox with firebricks the heat is reflected back into the firebox reducing heat loss and increasing heating. Made from quality fireclay to save the amount of coal used in the fireplace, by reducing the grate size, sides and one back-brick. A fire brick, is a block of ceramic material used in lining furnaces, kilns, fireboxes, and fireplaces. A refractory brick is built primarily to withstand high temperature, but will also usually have a low