8mm HEX HEXAGON SHAFT ( 5/16" ). ADAPTER SOCKET 5/16" (8mm) HEXAGON X 10mm SQUARE DRIVE FEMALE / FEMALE. NOTE: 8mm ( 5/16" ) HEXAGON DRIVE. BIG FLAT SLOT SLOTTED SCREWDRIVER INSERT BIT. EXTRA LARGE SCREWDRIVER BIT, BIG SCREWDRIVER BIT.
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