the applicant at the rear of the boot the shell 1 and the part 3 of the upper are joined by a connecting mechanism 6 comprising a lever 7 the bottom end of which is hinged by means of a pin 8 with the shell 1 and a middle point of which is hinged by means of a pin 9 with a link 10 the other end of which is by means of a pin 11 with the upper 3 the lever 7 passes through a recess in the upper 3 the pin 8 hingeably connecting the lever 7 to the shell 1 is mounted in a gap 12 for example between two ribs or inside a clearance the heel of the inner shoe not shown resting against 13 as described in patent application ch 174 86 of the applicant the lever has a protruding part 14 acting as a grip for the user so that the connecting mechanism 6 can be opened a metal part 16 is fixed inside a recess 15 located in the upper 3 and in the form of a compartment this metal part 16 consisting of a folded plate having at the top two parallel flanges 17 between which the pin 11 of the link is mounted more precisely this pin 11 is mounted in two opposite apertures 18 in the flanges 17 these apertures being oriented in the direction of the hinging points of the connecting.