Description: Using the advanced alloy steel, the overall induction hardening, not easy to wear. It is useful to operate electronic device, perfect for electrician, mechanic and repair work Corrosion resistance and oxidation resistance: not discolored, not easily scratched. Can easily suck the screws. The bit can be used in an electric screwdriver and the handle can also help to turn the screw manually. Can be used for an electric screwdriver, manual screwdriver, electric drill, and other group general tools. Specification: Set Type: Multi-functional Combination Set Material: Chrome Vanadium Alloy Steel Spinning Head Type: Cross System: Metric Scope of Application: Non-precision Maintenance Function: Combination Size Chart: PH2 10Pcs:50mm/1.97inch PH2 Series 7Pcs:25mm/0.98inch PH2 Series 7Pcs:50mm/1.97inch PH2 Series 7Pcs:65mm/2.56inch PH2 Series 7Pcs:70mm/2.76inch PH2 Series 7Pcs:90mm/3.54inch PH2 Series 7Pcs:127mm/5.00inch PH2 Series 7Pcs:150mm/5.91inch 6 Pieces:25mm/0.98inch 6 Pieces:50mm/1.97inch 6 Pieces:50mm/1.97inch Package Includes: 1 Set Drill Screwdriver Head(4 Pack) Note: 1. Please allow slightly error due to manual measurement. 2. Due to the difference between different monitors, the picture may not reflect the actual color of the item. 3. Wish you a wonderful on-line shopping!