10 PCS 1/4" - 3/8" - 1/2" DRIVE SPLINE & TAMPERPROOF SPLINE BIT SOCKET SET. TRIPLE SQUARE BITS ARE SUITABLE FOR USE WITH XZN® FIXINGS. 1/2" DR TAMPER PROOF: M14 - M16 - M18 ( LENGTH 55MM ). 1/4" DR: M4 - M5 - M6 ( LENGTH 37MM ).
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