10 Piece Spline Tip Bit Socket Set, M-Type, S2 and Cr-V Steel, Extra Long 4" Length, M4-M18, XZN Triple Square Spline Bit Socket Set. 1/2"Dr: M16 (tamper proof), M18 (tamper proof). Set includes: 1/4"Dr: M4, M5, M6; 3/8"Dr: M8, M9, M10, M12, M14 (tamper proof);.
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