1/4" shank. Single cut, cylindrical, cones, inverted cone, tree, oval, ball - pretty much what comes in a 6-8 piece set, but the cylindrical and tree shaped are probably the most important.
I use them for projects like porting cast iron headers, deburring, other automotive use and any projects that come up. Standard length. Thanks.
Last edited by High_Noon; 04/08/20.