For 1/4" square drive and tightening torques up to 25Nm:
Sizes 2 - 6mm.
For 1/2" square drive and tightening torques from 25 - 210Nm:
Sizes 6 - 14mm (short version 55 mm) and sizes 5 - 12mm (long version 100mm).
See photo for full contents. Comes in sturdy, welded steel box, powder coated for durability. With strong moulded plastic insert for the secure placement of each item.