Mutual Materials firebrick is manufactured to comply with the physical properties and characteristics specified by ASTM C 1261, Standard Specification for Firebox Brick for Residential Fireplaces. They are specifically designed for use in wood inserts or stoves and are not meant for exposed outdoor use, veneer wall or horizontal paving applications.

Mutual Materials firebrick is manufactured from a special blend of clay and shale to produce a hard-fired refractory brick capable of resisting the heat produced in a common fireplace.

Maximum recommended temperature: 2700 F.