This 18mm GearWrench socket pairs Surface Drive technology with a 1/2" drive square for high-torque fastener work on metric automotive, truck, and equipment hardware. Surface Drive contacts the flat faces of the fastener instead of the corners, delivering up to 25 percent more turning force and reducing the rounded-head failures that plague standard 6-point sockets on stuck or rusted bolts. Built from forged chrome vanadium alloy steel with a full-polish chrome finish, the socket meets ASME B107.5M for hand-ratchet metric sockets.

• Surface Drive geometry applies force to the flat faces of the fastener, not the corners, fighting fastener rounding and improving grip on damaged hardware
• 6-point hex broach for secure engagement on standard metric hex bolts and nuts
• Chrome vanadium alloy steel for high torque capacity and impact resistance
• Bright full-polish chrome finish resists corrosion and wipes clean of grease, oil, and brake dust
• Knurled identification ring distinguishes metric sockets from SAE by touch when working under a vehicle
• Hard-stamped size markings stay legible after years of shop use
• Chamfered opening guides the socket onto the fastener for faster placement
• 1/2" drive square accepts standard 1/2" ratchets, breaker bars, and torque wrenches up to typical 1/2" drive limits (about 300 ft-lb continuous)
• Meets or exceeds ASME B107.5M specifications for metric hand-ratchet sockets
• Size: 18mm

Tip: Used on M12 flange-head bolts (DIN 6921) common in European automotive suspension control arms, sway bar links, and engine mount brackets. For standard-hex M12 (DIN 933), use the 19mm socket instead.

1/2" vs 3/8" drive: Choose this 1/2" drive socket for fasteners torqued above roughly 80 ft-lb (lug nuts, large suspension hardware, axle nuts, crankshaft pulley bolts). For lower-torque engine bay work in the same size range, the 3/8" drive version is lighter and fits tighter spaces. Always use a chrome hand-tool socket like this with a hand ratchet or torque wrench, not an air or electric impact wrench - impact tools require black-oxide impact sockets that are heat-treated for impulse loading.