4-in-1 System, Compact, Straight Flexible Shaft, 12-Inch. The 4-in-1 System transforms to quickly switch between a Compact Right Angle, Standard Right Angle, Right Angle Flexshaft, and Straight Flexshaft. Withstand the power of today's impact drivers with the metal gearcase design and access tight spaces with its short 1.5 in. height.