Universal Joint Sizes: 1/4", 3/8", and 1/2" Dr.Drop Forged, Heat Treated Steel. Oil-Quenched, Black-Oxide Finish for DurabilityHoles on Two Largest Universal Joints for Locking onto Drive TangSpring-Loaded Ball Bearings Hold Sockets SecurelyBall/Swivel Action Universal Joints Gives Sockets Access in Tight Areas
Professional quality and it is specially designed for use with air tools
Brand: hobbytoolsupply