I made one of these for my air hammer and it works better than anything else I have tried.
The key to its success is that the tool does not provide any turning torque action which would destroy the fastener head. The turning action is provided manually by the handle.
The only thing which the air hammer provides is shaking loose the debris in the threads.
Once you get the bit on the fastener head, you slowly pull the trigger. Then you slowly move the handle back and forth by hand. Once it is free, you take the fastener off with a wrench or by hand.
It is particularly handy for clutch head screws.
