A central position of a water storage tank is provided with a drain opening; a water return bowl is in a short box shape, and is made of silicone; the bottom end of a skirt of the water return bowl is in direct contact with a bottom plane of the water storage tank to form a closed surface; a top plane of the water return bowl can attach to a grate, and the skirt of the water return bowl can be folded inwardly to form a curved flaky structure under drainage pressure; drain holes of the grate are provided on the edge of the water storage tank. Supports for supporting the grate are provided in the water storage tank. A gas buffer device is provided on the top surface of the flat-top water return bowl.

A removable cartridge for a low or zero water urinal outlet comprises a body comprising a side wall including one or more locking projections projecting out from the wall. One or more resilient elements are provided in the wall and each resilient element includes one of the locking projections.

A drainage fitting (10) is described. The drainage fitting (10) comprises a housing (12) adapted to be inserted into a drainage outlet, the housing defining a housing inlet (14) and a housing outlet (16) and a one way valve (18) adapted to be received within the housing (12). The one way valve (18) has a body defining a valve inlet (22), a valve outlet (24) and a valve passageway (26), the passageway (26) providing fluid communication between the housing inlet (14) and the housing outlet (16). The drainage fitting (10) further comprises a fitting insert (28) adapted to be located in the housing inlet (14), the fitting insert (28) defining an insert portion (30) adapted to extend through the valve inlet (22) and into the valve passageway (26). In the presence of a negative pressure differential, air can pass through the valve (18) to relieve the pressure differential, but in the event of a positive pressure differential, the insert portion (30) prevents the one way valve from inverting to relieve the pressure differential.

The present invention discloses a self-adjustable gas isolator, including a floater, a liquid storage device, a liquid outlet, a cover plate, a liquid discharging hole and a pressure balancing device. The floater has a pressure relief port; the pressure balancing device is connected with the floater in fixed position; the floater is sleeved in the liquid storage device and the floater goes up and down along with liquid level in the liquid storage device. The sealing device regulates the opening degree between the floater and the liquid outlet automatically according to the liquid volume discharged, and the pressure balancing device releases gas pressure preventing liquid from discharging, and the discharging speed of liquid is fast. The self-adjustable gas isolator is simple in structure, no components for hooking sundries in its channel, and is not easy to jam. When discharging liquid, the floater swings or rotates with self-cleaning function.

An apparatus for a urinal is described. The apparatus comprises a plate member adapted to form a seal with a urinal outlet, the plate member defining a throughbore permitting the passage of liquid, in use, from the urinal to a soil pipe and a diaphragm located in the plate member throughbore, the diaphragm adapted to permit the passage of liquid through the throughbore in one direction only from the urinal to the soil pipe.

A siphon includes a bypass. The siphon includes an upper section having a top coupling for connecting to a drain outlet and a side drain opening having coupling for connecting to a wastewater utility pipe. The siphon upper section is facilitates direct flow via the side drain opening, thereby to bypassing a basin of the siphon. Thus, substantial volume of accumulated water is evacuating directly into the wastewater utility pipe.