or interlocking connection or snapping in of the ends during the widening step of the b after successfully mounting the bellows on a shaft end as shown in fig6 and 6 a only the press or contracting ring or the pre mounted mcr then need to be clamped or compressed once again as an example fig9 shows such an installation that is suitable for contracting pre mounted mcrs in this procedure the lock of the contracting or press ring attached in the pre mounted status is sealed such that it can no longer be automatically opened or separated the installation 40 shown in fig9 has described in simplified manner clamping segments 41 able to be actuated annularly inward and together displaying an annular opening 43 with their inner contours with a hydraulic or pneumatic installation 42 the individual clamping segments 41 can be pressed or driven radially inward in order to reduce the diameter of or contract the contracting or press ring the present new development thus includes clamping or contracting rings or so called multi crimp rings mcr with open ends and known mechanical lock due to the fact that these mcrs are produced with open ends they can be manufactured with corresponding pre stress this pre stress causes a spring effect in the direction of the ring center this spring effect can be used to the effect that the ring automatically holds will no structural adaptation on the bellows in the area of the end collar in an appropriately provided groove e g provided for receiving mcrs this is because as is well known practically every model of bellows is manufactured with the aforementioned groove this groove can be designed running throughout or also as just an individual cam arranged on the.