Wrench S-Shape Box End Metric 12 pt 12 mm Each end has different curvature signatures for access in multiple areas. N-PowerFit Drive- Increased strength and reduces rounding or fastener damage by distributing stress through a gentle arc in the bore by enlarging the contact surface. . Designed for maximum strength with minimal wall thickness made possible by tough materials, advanced processing technology, and optimal heat treatement.. Clear engraving- The beautifully-refined engravings are easy to see and increase the efficiency of work.. Approach fasteners from 4 different directions NM12-12