WIRQUIN NEO AIR, allows the pipes to be naturally ventilated. When negative pressure is created in the pipes, WIRQUIN NEO AIR's membrane rises and thus creates continual ventilation to prevent suction of the depth of seal. Anti-Vacuum Function. TECHNICAL CHARACTERISTICS for the 80mm WATER SEALFLOW rate L/min: 59,6L /min.DEPTH OF SEAL: 80 mm ADJUSTABLE HEIGHT: 175>235