MX ERGO, an ergonomic trackball mouse. - Model Name: MX ERGO - Brand: logi - Color: Gray - Features: Ergonomic design - Type: Trackball - Charging Type: micro USB Thank you for viewing. I've been using this for about 2-3 years, but I'm selling it because I recently purchased its successor. Trackball mice are very comfortable once you get used to them. I cleaned it about once a week, so there's no ball sticking, and it moves very smoothly. It supports two types of connections: USB receiver and Bluetooth. It's been used quite a bit, so there are corresponding scratches and dirt. Please understand that this is a used item before considering a purchase.