UniGuard is a low-profile, waterless, one way drain valve for recreational vehicles that is used instead of the standard P-trap to guard against and protect the living space from foul orders of the recreational vehicle drain system. UniGuard opens under the water pressure of a draining fixture and the specially designed Silicone rubber bladder closes to form a tight, odor proof seal after the fixture has discharged. Includes 1-1/2” female threaded and 1-1/2” male threaded connections