Logitech Trackball M570 + Keyboard K275 Set I used these together, but I'm selling them because I've replaced my keyboard and mouse. They connect wirelessly via Logitech Unifying, so you can connect both devices with a single receiver, which is convenient. Please understand that these are used items before purchasing. Logitech M570 An ergonomic trackball that provides comfortable operability. - Model Name: M570 - Color: Black/Blue - Brand: Logitech - Connection: Wireless (Unifying) - Power... Battery powered Logitech K275 A full-size wireless keyboard with a stable connection and Japanese layout. - Model: K275 - Size: Full size - Connection: Wireless (Unifying) - Language: Japanese layout