These red collet clips are placed on plastic plumbing pipes in order to indicate that the water inside the pipe is hot.
FloPlast Flofit+ Push Fit Collet Clip Blue Cold Water - 15mm - Pack of 10
FloPlast Flofit+ Push Fit Collet Clip Red Hot Water - 15mm - Pack of 10
FloPlast Push Fit Waste Socket Plug - 32mm Black
FloPlast Push Fit Waste Pipe - 32mm x 3mtr Black
FloPlast Push Fit Waste Bend - 135 Degree x 40mm White
FloPlast Push Fit Waste Tank Connector - 40mm Grey
