Description: High hardness & non- , large torque & long life and durable. The screwdriver head can lock the connecting rod with magnetic. Change external six angle into internal six angle - Strong Practicability. Great for exchanging the sleeve and the joint, prolonging the connecting rod. 1/4" quick-change hex shanks fit any standard size screwdriver bit, 1/4" impact drivers and hand-held drivers. Widely used in situation of narrow space, to reach the work-place where hands can not reach. Specification: Color: Silver + Black Material: Aluminium tube, stainless steel Shank Shape: Hex Shank Sleeve Significant Depth: 11mm / 0.43" Diameter of Shank: 6.35mm / 0.25 " Diameter of Sleeve: 10mm / 0.39" Package Includes: 1 Piece Bit Holder (6 Pack) Note: As different computers display colors differently, the color of the actual item may vary slightly from the above images. There is 2-3% difference according to manual measurement. Please check the measurement chart carefully before you buy the item.