You're welcome
This is the grinders I have been using...
http://www.ebay.com/itm/IR-Air-Right...item4cfe2f75ed
A friend, who is a mechanic by trade, swears by these, but he uses some special tool from IR to oil properly.
http://www.ebay.com/itm/IR-3102-Supe...item3cb920a0e2
If you look on the head, you'll see where you have to oil it to get proper life from the tool.