TEKTON 14202 3/8-Inch Drive by 21 mm Deep Socket, Cr-V, 6-Point 6-point opening snugly fits hex-shaped fastener heads to apply maximum torque without slipping Advanced design grips flat sides of fastener heads, not corners, to prevent round off Extra-deep broach reaches over long, threaded shafts to access nuts Detent notches in drive end lock onto ratchets and extensions Made from premium chrome vanadium steel with a durable mirror chrome plated finish