Black oxide coating protects the sockets against rust and corrosion. Each adapter is small enough to reach narrow areas. Its a great set for drivers, wrenches and ratchets to convert size up or down for your automotive needs in the garage.Q: Is this adapter a 1/2 " drive?A: This set of adapter reducers consists of 1/4" to 1/4", 3/8" to 1/4", and 1/2" to 1/4".