Inexpensive and worth having.

I bought the 1/2" drive about six months ago and I just added the 3/8" to my wishlist. The purpose of this tool is to get a socket or socket bit on the end of your air hammer and turn it with a wrench while you "shock" it. The difference between this tool and an impact wrench is that the user has more "feel" and can apply the torque independently of the shock for removing smaller or fragile fasteners. I operate the air hammer with my right hand and use my left hand to apply light torque on the wrench at first and then gradually increase the torque until the fastener breaks loose. In contrast, an impact wrench bangs and spins hard and fast so you might strip or snap the fastener in a fraction of a second. I'm a bicycle mechanic so I use this tool most often for loosening stuck T25 Torx head bolts that secure the brake rotor to the hub. I've also used it with a 1" or 1-1/8" socket to tickle headset bearings that were sweat-skanked into the frame so they just lift out in one piece. If you already have an air hammer then this is a great inexpensive option to get more use out of it and maybe save the day. It works especially well for shallow "female" fastener heads like Phillips, Torx, Allen that need a little finesse to remove. My only complaint is that there is no hog ring or spring ball so the sockets just fall off of the tool.

Works good. I would prefer if it had a ball detent or hog ring on the end to help hold sockets though.

Works well but the way its designed allows for wrench to slip off easily