Stanley 92-574 MaxDrive 15 Piece Locking-Flex Ratchet System The MaxDrive System comes with a 3/8" Socket Driver Adapter, 1/4" Bit Driver Adapter, and 12 Drive Bits The interchangeable head offers users a multifunctional bit driving and socket system that can be incorporated with any style 1/4" bits or 3/8" sockets All MaxDrive System ratcheting wrench heads and open end wrench head are compatible with the MaxDrive System Ratchet Features a Locking-Flex Head Ratchet System. Ratchet Supports 15 Different Positions Limited Lifetime Warranty