HL60 is a natural repair mortar specifically formulated for the patching and restoration of limestone. Designed to decrease significantly the time required to complete stone repairs, HL60 can be ready for sculpting in 3 hours at room temperature. HL60 is a mineral-based, single component product that is mixed with water. It is formulated using only natural binders; no synthetic polymers or additives are used. HL60 has excellent freeze-thaw and salt resistance. It is vapor permeable. Skilled masons can easily apply HL60; no special certification is required. Weight: 48 lbs