Quickly change between 1/4in. and 5/16in. hex sizes with Malco's unique, exclusive, dual-sided magnetic hex drivers. The reversible hex socket fits over a 1/4-inch magnet-tipped, ball locking hex shaft, and can be quickly reversed to change sizes. Eliminate troublesome buildup of metal shavings in the hex tip with the “Easy Clean Magnet”. Just swipe with a glove or shop towel to clear any metal shavings. Tested torque of the reversible hex chuck driver design is equal to one-piece drivers.