Two-body collar accessory adaptable to the outside diameter of the drinking water main pipe. Consisting of the collar, union elements and seal. The upper T-shaped mount allows the coupling of a PE pipe that reaches the household connection, it also has a built-in tubular element with cutting edges which moves through the internal thread that allows it to reach and cut to the pipe of the potable water distribution network that is with or without load. The cutting tool must remain inside the upper mount of the collar without obstructing the passage of water, its actuation also allows the cutting to operate as a closing and opening valve.