cover 2b and the loading aid 30 a further positioning device 41 with a positioning device part 41b associated with the housing part and with a positioning device part 41a associated with the loading aid 30 which together permit the correct position to be compared visually or in a positive locking engagement manner or necessarily produce the correct position mechanically in the present embodiment two holes 42 are provided in the strip like carrier element 35 the size and diameter of the holes being adapted roughly to the size of the bearing axes 19 and preferably being somewhat larger in this way the loading aid 30 can after optically checking be aligned in a simple and quick manner in the transfer starting position another embodiment of the positioning device 41 is similarly accomplished according to fig3 to 6 in this embodiment the positioning device part 41a is formed by two spaced apart projections that cooperate in positively locking manner with two counter elements arranged on the cover 2b or alternatively is formed by a non circular projection 43 that is arranged on one side of the application part 16 and may serve both for the positive locking engagement positioning of the application part 16 on an associated side wall 13 and for the positioning of the loading aid 30 by engagement in a recess.