Coprox waterproof additive is an excellent primary waterproof hen mixed with mortar, scree damp reinforce concrete, or plaster it is an essential ingredient in the construction of structural retaining walls. floors, shower ,basements, wine cellars, under ground, parking, ponds swimming pools, reservoirs , and water futures for the protection of raising falling and penetration of damp. also coprox waterproof is an excellent remedy for the plugging of leaks.