This sale is for a really excellent RC401 cable release adapter to allow fitting of any standard threaded cable release to the later Mamiya 645 Super / Pro / ProTL cameras. Also usable with all RZ67 cameras if you want to, although there is no need unless you have a damaged cable release socket on your camera body. It is in really excellent condition.
This adapter fits into the electronic release socket on your camera body and avoids the need to have a special Mamiya electronic release cable. Simply screw any standard threaded release into the adapter and away you go. This example has only very minor signs of use. Hard to find.