Teng Tools Combination Spanner Set Anti Slip TT1 12 pc Cordless_Die Grinder Using the same designed screw Using the same designed screw tip as from an auger drill bit the 4 flute boring bit feeds itself Not intended for raw or unfinished surfaces Supplied in the unique Teng Tools TC tray with removable lid and dove tail joints for use on its own or as part of the Teng Tools TC control system 12 piece metric combination spanner set featuring a typically Teng new design in combination spanners that gives an anti slip grip on the open end as well as the Teng Tools hip grip function where the spanner drives on the flank of the fastening rather than the corner