TL Derringer handles

I bought a set when I needed short ones after I flatbeded my truck
I had a few sets of old happijac `s , so I used the front spring loaded ones ,added a short length of stainless all thread and a lock washer between the nut against the happijac body so they cant be turned loose with out a wrench , so they can be locked
That's the difference in fast guns ,they cant be loosened once there locked
Torklift changed the derringers some time ago to be aluminum , what`s not alum is stainless , no rust