This is a receiver for a Logitech trackball mouse. The mouse itself is broken, so I am selling only the receiver. ■ Product Information Unifying Receiver C-U0007 Logicool (Logitech) Can connect up to 6 compatible devices. ■ Condition This receiver was included with a trackball mouse (M570t) purchased in 2016. Operation confirmed. I connected another trackball mouse (M575S) and it worked normally.