Abstract: A backflow prevention device includes a piston received in a device passage between an inlet port and outlet port. A relief port can fluidly communicate with a middle segment of the device passage. The piston is movable between a normal flow position in which the piston blocks fluid communication between the relief port and the middle segment of the device passage and a backflow position in which the piston allows fluid communication between the relief port and the middle segment of the device passage. The piston can move to the normal position in response to normal flow through the device passage from the inlet port toward the outlet port and configured to move to the backflow position in response to greater pressure in the middle segment than in the inlet port.

Abstract: A backflow prevention device includes a piston received in a device passage between an inlet port and outlet port. A relief port can fluidly communicate with a middle segment of the device passage. The piston is movable between a normal flow position in which the piston blocks fluid communication between the relief port and the middle segment of the device passage and a backflow position in which the piston allows fluid communication between the relief port and the middle segment of the device passage. The piston can move to the normal position in response to normal flow through the device passage from the inlet port toward the outlet port and configured to move to the backflow position in response to greater pressure in the middle segment than in the inlet port.

Abstract: A plumbing fitting assembly includes an anchor member for being received in a transverse hole in a structure. One end of the anchor member is externally threaded and the other includes a catch portion for engaging a surface of the structure adjacent the hole. The threaded end is threaded into a clamping member configured to form a seal with the opposite surface of the structure or another liquid conveying structure. The anchor member can include a tool formation for mating with a rotating structure of a tool. The assembly can include a lock ring for being lockingly received in an interior passage to prevent the catch portion from deflecting inwardly when installed. The plumbing fitting assembly can also be configured for forming a plumbing fitting at a transverse hole in a flexible, liquid-impermeable panel.

Abstract: A plumbing fitting assembly includes an anchor member for being received in a transverse hole in a structure. One end of the anchor member is externally threaded and the other includes a catch portion for engaging a surface of the structure adjacent the hole. The threaded end is threaded into a clamping member configured to form a seal with the opposite surface of the structure or another liquid conveying structure. The anchor member can include a tool formation for mating with a rotating structure of a tool. The assembly can include a lock ring for being lockingly received in an interior passage to prevent the catch portion from deflecting inwardly when installed. The plumbing fitting assembly can also be configured for forming a plumbing fitting at a transverse hole in a flexible, liquid-impermeable panel.