This Universal Speedball Only from MID49 is compatible with other 1" ball attachment systems. The accessory mounting end features a 1/4"-20 threaded screw with a 3/8"-16 threaded sleeve, allowing you to mount an accessory with either a 1/4"-20 or 3/8"-16 mounting hole without having to swap ends or use thread adapters. With this system, you have instant access to either mounting standard for fast and secure mounting. Just press the 3/8"-16 sleeve down to use the ¼"-20 threaded screw for mounting. The Universal Speedball Monitor Mount features individual locking levers for tightening accessories on each ball joint end, providing extra torque to keep your accessory from twisting.