An inflow fitting for the filling of a cistern comprises a housing, a water conduit disposed in the housing and having an entry and an exit, a float-controlled valve, which is disposed in the water conduit and which shuts off the water conduit or opens it up in the filling operation, and a float, which cooperates with the valve, for controlling the valve, wherein the float has a cavity, which is fillable with water, and at least one buoyancy chamber. The inflow fitting further comprises a supplemental water tap, branched off from the water conduit, for filling the said cavity in order to provide an additional weight. In the water conduit, in the region of the supplemental water tap, is arranged at least one backflow element, with which a backflow can be provided in the region of the supplemental water tap for the pressure-independent removal of supplemental water.

An inflow fitting for the filling of a cistern comprises a housing, an outlet pipe, and a water passage formed in the housing and outlet pipe and having an entry and an exit, a float-controlled valve, which is disposed in the water passage and which shuts off the water passage or opens it up in the filling operation, and a float, which cooperates with the valve, for controlling the valve, wherein the float has a cavity that is fillable with water, and at least one buoyancy chamber. The inflow fitting further comprises a supplemental water tap, branched off from the water passage, for filling the said cavity in order to provide an additional weight. In the water passage, in the region of the supplemental water tap, is arranged at least one backflow element, with which a backflow can be provided in the region of the supplemental water tap for the pressure-independent removal of supplemental water.

A backflow prevention device including a tank inside of and moveable relative to a housing. A cap coupled to the housing and including inlet and outlet chambers fluidly connected through an inlet, the outlet chamber communicating with the tank. A shell is connected to the cap and includes a shell inlet chamber, which communicates with a first outlet hole of the inlet chamber, and a second outlet hole, which communicates with the tank. An inlet sealing member opens/closes the inlet to fluidly connect/disconnect the inlet chamber and the outlet chamber; and an outlet hole sealing member is moveable with the tank to open/close the second outlet hole. Closing the second outlet hole prevents water from flowing through the second outlet hole and switches the inlet from open to closed. Opening the second outlet hole allows water to flow through the second outlet hole and switches the inlet to open.

In one aspect, a tube device including concentric inner and outer tubes to form an annulus to receive an upright stem in a toilet tank and adjustable vertically and rotationally relative to the stem. In another aspect, an elongated catch device is pivotally mounted intermediately to an inlet tube device and carries at its upper extremity a keeper selectively disposed in the path of a float device to, unless a toilet has been flushed, block lowering of the float device and consequent opening of the control valve.