Abstract: A sealed, shaped watch-case has a rim formed with a rectangular interior defined by a wall in which a annular groove is formed around the rim interior. The watch movement is supported in the rim by an elastically compressible retaining ring held in compression axially of the case by a circular, annular retaining part formed with radially outwardly extending projections. These projections are insertable into the rim by disposing them at corners of its rectangular interior until they are level with the groove so that rotation of the retaining part locates them in the groove to lock the retaining part in position. The case also has a base welded to an annular frame which is an interference push fit on the retaining part.