Loaded with the most popular bits used in automotive work, including a 1/4" socket adapter, this driver is a must for the professional mechanic or anyone who works on their car or truck. The valve stem bit is also a standard bit-type in the HVAC industry. The shaft opening serves as a 1/4" hex driver. Handle is made from engineered nylon/ABS resin, Triax 1120. Alloy steel shaft. Makes it EZ 2 find, change and store bits. Seven double end bits give you the 14 most popular screwdriver tips. Palm saver cap: Does not turn as you push on the cap and turn the handle to drive screws. No blisters in the palm of your hand. EZ guide collar: Helps maintain full contact between the bit and the screw for easier screw driving. Provides greater control. Drivers made in USA. Phillips bit sizes 1-2. Square bit sizes 9-10, 15-20, 25-27, 30-40. Flat (slot) bit size 5.5. 1-3/8" Diameter. 11-1/2" Extended length.