RD - N back pressure spraying slurry is  the two components, after mixing, the besmear after curing, forming half just half soft coating, at the same time to the penetration in concrete, form a double seal, separately used as a garage roof slow infiltration processing, can be resistant to 2-4 m deep water column back pressure. The pressure, to change of 0.6 mm crack. A garage roof water leakage management, special waterproof impermeability slurry spraying YYA first, spraying RD - N back pressure again Tuling pulp, sealing reliability of 97%.