Reducing niplexes are adapters which, when mounted on a bar feeder of an automatic, CNC or sliding headstock lathe, are able to use different types of thrust collets with different threaded connections. This adapter offers excellent flexibility when selecting and purchasing different models of thrust collets for fixed headstock or sliding headstock CNC lathe loaders. The adapter is mounted on the rotating part of the loader via its threaded connection, the second thread is used to clamp the pusher gripper to the adapter and thus have the possibility of using two different types of pusher grippers with two different threaded connections. Since an adapter has been applied between the rotary gripper and the push gripper, the assembled assembly has a longer total length, ranging from 15 mm to 25 mm. In this case, it is best to check that the distance between the surface bar and the surface of the main collet is in the correct position after first loading the bar into the lathe.