A friend gave me small box full of lathe toolbits a while back. Today I was cleaning out a drawer and uncovered them. There a half dozen bits that are marked "Micro 100 BT- 4 thru 7. I spent a little time looking on the web and then the KBCTools catalog and could only come up with a name, nothing on How to use them. Can any one tell me any thing about them. Which side is up or how they are used?