Loctite PL Polyurethane Concrete Crack and Masonry Sealant is a premium quality, commercial grade sealant developed especially for forming permanent, water and weatherproof seals in all exterior gaps and joints. This sealant is elastic and remains flexible to expand and contract with construction material movement to protect and retain the original seal. Loctite PL Polyurethane Concrete Crack and Masonry does not require a primer for concrete, brick, stone or masonry and resists deterioration from weather, stress or movement.