This is an angle adjustment stand specifically for the Logicool ERGO M575 and M575SP. It secures in two places: the battery cover and the ball's recessed area. By tilting it more than the standard angle, it allows for work at a natural hand angle. The receiver can be stored inside or on the back, depending on how you use it. You can turn the power on and off without removing the stand. *Trackball mouse not included.