Klein Tools 630M 3" Hollow Shank Magnetic Tip Nut Driver Set (2 Pieces) Hollow shaft design with Rare Earth magnetic tip facilitates work on bolt applications Set contains: 1/4-Inch (630-1/4M) and 5/16-Inch (630-5/16M) hex sizes Handle end is color coded for easy identification Cushion-Grip handle allows for greater torque and comfort Internal flanges provide solid, twist-resistant shaft anchor