Every now and then Harbor Freight has something that turns out to be really useful. I picked up this impact screwdriver to remove the screws in the Jeepster door hinges. I've had a set of 'screw knockers' for a long time (they work with a pneumatic impact hammer) but I like this better. Works good on 9" brake drum screws and rusted bolts. The hex bit adapter is 1/2" square drive. I used it to loosen the exhaust manifold nuts on my F-head. Worked on all but one. Hint - drill out the center of a couple of nuts and stack them inside the the socket so that the shock of the hammer strike hits the nut at the same time that the driver applys rotating force.