This unique, exclusive, (U.S. Patent Pending), double-duty chuck driver ensures that popular 1/4-inch and 5/16-inch magnetic hex drives are always at hands reach. The dual-sided hex socket fits over a 1/4-inch magnet-tipped, ball-detent locking hex shaft and is quickly reversed for changing sizes. Tested torque of the socket and shaft is equal to comparable one-piece single size drivers to ensure optimum screw performance. The removable, reversible socket also allows easy access for cleaning the magnet tip to eliminate any troublesome buildup of metal shavings in the hex opening. Positive engagement of hex head fasteners is never compromised.