This 3-Piece Carbide Insert Boring Bar Set includes right hand indexable solid steel boring bars that use 1/4-Inch, 80Degree diamond inserts (CCMT21.51, CCGT21.51, CCMT060204, or CCGT060204). Features negative 7Degree end and side cutting angle. Includes 5/16-Inch x 4-Inch, 3/8-Inch x 6-Inch and 1/2-Inch x 8-Inch boring bars. Set comes with Torx wrench and fitted aluminum case with handle.