3/8" Drive 6-Point Metric 21 mm Flank Drive® Semi-Deep Impact Socket | IMFMS21 General Service Set (Blue-Point®) (1/2") lb (kg) (ball bearing) :

lb (kg) (ball bearing) : 120 (54)

• Retaining ring holds spark plug in socket to aid in removal and installation

• JKRR33W55A Rubber Work Surface with raised edges

Outside Dia : 4-13/32

3/8" Drive 6-Point Metric 21 mm Flank Drive® Semi-Deep Impact Socket | IMFMS21 General Service Set (Blue-Point®) (1/2") lb (kg) (ball bearing) :Snap on impact sockets are heat treated to optimize impact service life with a lower hardness than hand sockets and are able to withstand repeated cycling loads of impact wrenches Snap on uses a proprietary blend of special alloy socket steel that provides long life and great strength Flank Drive wrenching system delivers up to 20% more turning power without slipping or rounding while exceeding ANSI performance standards Industrial, black oxide,