The MEGAPRO 15 in 1 ShaftLOK Screwdriver outperforms the best screwdriver set when it comes to it's compact yet versatile application. The locking shaft eliminates the danger of bits falling out of the shaft when getting partially "stuck" in the fastener. 6a ^2 & 10a ^2 Locking Extensions lock into the ShaftLOK screwdriver shaft providing a slim profile into those hard to reach places. 0.375a ^2 (9.6mm) min. clearance. Link multiple extensions together for extra long reach. Loaded with 7 double end professional quality bits, this assortment of bit types and sizes provides the 14 most popular tips for driving screws. The shaft opening serves as a 1/4a ^2 hex driver! Hence the name "15-in-1a ^2. Specifications: Weight: .5 lbs Driver Features: EZ Guide Collar, Locking Bit, Palm Saver Cap, Retractable Bit Cartridge Screwdriver Bits: Square, Phillips, 1/4a ^2 Hex Shaft, Flat, Torx Warranty: Lifetime Warranty Made in: USA