This pair of parts antennas are the exact parts you will receive. I do not know the reason why they do not work. I did not take the time to test each component so there are no guarantees. You may or may not be able to make one good one from the two, but if you have another in your SL that is not working you may be able to use parts from these to fix your existing Hirschmann power antenna. Priced accordingly.
If you are trying to restore your original metal case antenna these parts will help!
R107 Late 450SL Early 380SL Pair of Hirschmann Parts Antennas - USED $95.00Sale