frame and inserted into a notch cut out in the dial frame 2 further includes a third seat 18 on which rests a bead 19 forming part of the movement 6 thanks to this arrangement the movement is axially held in place since on the one hand its bead is supported on seat 18 and on the other hand its upper face is retained by dial 7 itself held by the overhang 17 of bezel 4 finally frame 2 exhibits a fourth seat 20 in which is inserted a flange 21 forming part of the back cover 3 when the back cover 3 is applied the flange 21 will compress the portion of material 22 forming the frame 2 against caseband 2 thus assuring sealing of the case by its portion back cover caseband the explanations which have just been given are generally applicable to the various embodiments shown by figures 1 2 and 3 such figures differ from one another initially by the type of movement 6 employed calibre then by various details which are now to be reviewed fig1 shows a construction employing an electronic movement 6 the height of which is 3 mm this giving for the total.