The Expert Metric Short Arm Hexagon Keys are manufactured from chrome vanadium steel for increased torque strength that exceeds current standards. They have a black zinc plated finish. Micro chamfered angles on the end faces provide increased grip in the screw head.Conform to ISO 2936 - DIN 911.This Expert Metric Short Arm Hexagon Key has the following dimensions:Size: 3mmArm Length: 66mmL Length: 23mmWeight: 6g.