If you are going to be hammering on tools.....this is the most productive tool to own. I don't know how you ever get the Phillips head screws out of an engine case on a motorcycle without one of these. Only $ 23 at Sears....and yes Harbor Freight most likely has a cheap version for less.
It works with the screw inserts, or any 3/8" drive socket. You really need one of these if you are going to work on motorcycles...it was one of the first tools I ever owned, and I am still using the one I bought in 1972. (Although I have had to buy a few replacement bits over the years).
You just insert the bit of your choice and place it on the fastener, hold onto the tool with your left hand like you are trying to turn the tool in the direction of removal and hold it tightly into the fastener, and then hit the end hard with a hammer. The tool transforms the impact force into a rotational force. The tool will work in either direction, and you have to make sure the tool is set for the direction you want it to move by twisting the tool in the direction you want to go.
https://www.youtube.com/watch?v=DUOghfo7VGI If you own a motorcycle, especially one with the 'phillips' screws that are NOT philips,you need one of these babies, they are worth their weight