Incrementally extendable telescopic mounting, the extension of which is determined by a guide lug, integral with a female element and moving inside a multi-segment cam-type guide system, laid out at the periphery of a male element, and by the relative positions of a single cylindrical arc shaped stop having a trapezoid cross-section and being laid out on one of the telescopic elements, the trapezoid perimeter bearing surface of said stop resting successively on a circumferential series of staged cylindrical arc shaped hollow stops laid out on the other telescopic element and preferably having the same angular length, the same radial depth and the same trapezoid perimeter and area as those of the single stop, said single and multiple staged cylindrical arc shaped hollow stops having preferably, within their respective telescopic elements, the same outer and inner diameters and, as their common center, the device axis.