67 are bent upwards the edges 68 can also be bent somewhat to form supporting points for the sheet metal body fig7 shows a ball bearing having a tapering centre bore the fastening sleeve which is used here for fastening the bearing is designed with two sheet metal bodies 71 and 72 at the plastic moulding operation these two sheet metal bodies have been centred in mainly exactly the same way as described with references to fig1 and 2 the warts 73 will guide the bodies against central moulding mandrels whereas the opposite ends 74 and 75 have circular metallic guides in the moulding forms fig8 finally shows two cooperating sleeves 81 and 82 where the sheet metal body 83 of the inner sleeve has been designed with threads 84 at one of its ends these threads 84 cooperate with the teeth 85 designed in the form of threads on a clamping device 86 which has been stamped from sheet metal the fastening sleeve according to the present invention is very inexpensive to manufacture due to the fact that the sheet metal body is designed with stops in form of bulgings sheet metal lugs which have been bent upwards or the like the insertion of the sheet metal body in the moulding form is very simple to effect and the entire moulding procedure will be swift the mechanical strength of the fastening sleeve will be very high depending thereon that the comparatively small volume of.