DAP® High Heat Fire Resistant Mortar is a non-combustible silicate cement used for patching chipped firebrick in fireplaces and sealing wood-burning stoves. Adheres firmly to the firebrick when wet or dry. Sets rock hard when fired. Can also be used for applications in wood frame construction. DAP® High Heat Mortar is not a fire-rated sealant as defined by Underwriters Laboratories and is not appropriate for fire-rated applications. Interior use only.