Version :
Forged from high quality steel, internally bevelled for easy fitting to bolt heads. Square socket drive with close tolerances for secure fit on the drive attachment. Internal square to DIN 3120. The Surface Drive socket opening allows a tight fit and higher effectiveness. The pressure works directly on the faces of the nuts and bolts; weaker corners are protected. Intermediate sizes e.g. in inches (A/F, BSF, BSW) and rounded heads can be tightened or loosened using the Surface Drive.

Standard :
DIN 3124

Material :
Chrome vanadium steel, chrome-plated.