Expert BRIE113916B Metric Short Arm Hexagon Key 4mm 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: 4mm Arm Length: 74mm L Length: 29mm Weight: 10g