SPECIFICATION: 1/4in drive has M4 M5 M6, 3/8in drive has M8 M9 M10 M12 M14, 1/2in drive has M18. A total of 10 pcs bit sockets for you to use. 1/2in Drive: M18. CRV MATERIAL: These spline bit sockets are made from vanadium steel, with high strength, ensures excellent durability.
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