I've used it for about 2 hours... I couldn't get used to the trackball, so I put it away in a dark place, but I'm listing it now during the winter break. It's in pretty good condition, so I hope someone who likes trackballs will use it. Wireless, USB rechargeable trackball mouse. - Brand: Kensington - Model Name: Pro Fit Ergo TB550 - Type: Trackball - Connectivity: Wireless - Compatible OS: Windows, macOS - Power: USB Rechargeable