Material and durability Made from steel, this drill bit extension set is stable and strong, able to withstand pressure and resist issues from contact with oils or other fluids. Vast assortment for different tasks Includes 8 pieces of bit driver extension holders and 8 bits. Four sizes: 12 in (300 mm), 6 in (150 mm), 4 in (100 mm), and 2.5 in (65 mm); two pieces per size to cover a broad range of tasks. Suitable for daily use or replacement needs. Magnetic design for reliable retention The bottom portion of the hex bit extension is magnetized, keeping screwdriver bits steady and firmly fixed on screws. Helps prevent bits from falling off and improves work efficiency. Ideal drill bit extender with compatible interface The 1/4 inch driver adapter and 1/4 inch hex shank are an ideal fit for the included bits. Provides a firm and secure connection for drilling and driving, enhancing overall efficiency and safety. Use scenarios Furniture assembly or cabinetry work where extended reach improves efficiency and reduces effort. Installing shelves or mounting hardware in tight or limited spaces. Automotive or machinery maintenance that requires long reach and reliable bit retention during drilling and driving.