T&E Tools "Greater Surface Contact" on the flats of the hex (away from corners) gives a more positive non-slip, non-burr grip with increased torque strength.

Sizes: 10mm, 11mm, 12mm, 13mm, 14mm, 15mm, 16mm, 17mm, 18mm, 19mm, 21mm, 22mm, 24mm, 27mm.