To enable an easy connection with another pipe to be carried out and also their removal to be performed by a method wherein an end part of a female pipe having an end part of a male part of another pipe inserted and connected is provided with a fixing window, a slide member is fixed to it and the slide member is moved.

A leaf spring 9 is formed with a claw 11, a base floor part 12 and a connecting part 13. The claw 11 is directed downwardly from the base floor part 12, inserted into an inner bead of a male part of another pipe and connected to it. The base floor part 12 is provided with an engaging projection 14 and aligned with an engaging projection 8 of the main pipe 1. A slide part 10 is fixed in such a way that it may hold the base floor part 12, and connected to the main pipe 1 through the connecting part 13. The engaging projection 15 of the slide part 10 is pushed with a finger so as to be freely slid in a forward or rearward direction, the engaging projection 16 at the extremity end is inserted between the engaging projection 14 of the leaf spring 9 and the engaging projection 8 of the main pipe 1. It is rigidly connected to another pipe by engagement with the slide part 10 and a pushing-down of the claw 11 of the leaf spring 9. With such an arrangement as above, mere pushing of the engaging projection 15 with one finger enables a pipe to be easily connected or removed.