I purchased this about a year ago on Mercari. According to the previous owner, they used it for about two years before that. I am selling it because I bought a new mouse. I lost the Unifying receiver, but I was using it with Bluetooth. I have confirmed that it works. Please refrain from purchasing if you are sensitive to used items, as it has been stored by a regular person. *There is no box. Although not pictured, I will include a used AA battery if you would like. "Logicool M575S BLACK" ⚫︎ Trackball Mouse Height: 134mm Width: 100mm Depth: 48mm Weight: 145g Uses one AA battery ⚫︎ Number of buttons: 5 (left/right click, back/forward, scroll wheel with middle click) Type: Mouse Cable: Wireless (radio) #LogitechInternational #Logicool