ITEM NAME:3x Screwdriver Bit Holder Hex Shank 1/4" Quick Change Drill Bit Extension Set Descriptio n Description: Made of chrome vanadium steel, strong and long-lasting Interface has a locking mechanism, built-in magnetism, and automatically ejects the batch processing head Suitable for transfer of drills, screwdrivers, bits, etc. Extend various screwdriver heads and change the use of screwdriver heads Greatly improve work efficiency Specifications: Material: Chrome vanadium steel Colour: Black Extension Bit Holder Diameter : 6.35mm Extension Bit Holder Length: 60mm, 100mm, 150mm Package Included: 3Pcs/Set Hex Shank Screwdriver Extension Bit Holder Note: 1.Due to the manual measurement and different measurement methods, the actual size could be slightly different. 2.Please be reminded that due to lighting effects and monitor's brightness/contrast settings etc, the color tone of the website's photo and the actual item could be slightly different. 3x Screwdriver Bit Holder Hex Shank 1/4" Quick Change Drill Bit Extension Set.Extend various screwdriver heads and change the use of screwdriver heads. Extension Bit Holder Length: 60mm, 100mm, 150mm. We'd like to settle any problem in a friendly manner. Colour: Black. Greatly improve work efficiency.