This item is unused. Therefore, unlike other used sellers, it still has the shock-absorbing sheet between the trackball and the base (the sheet needs to be removed for use). I will also include a highly-rated Comfy mousepad as a set. This is also unused, but the mousepad has some small fibers attached to the back since I purchased it. Please let me know before shipping if you don't need the mousepad. SlimBlade Pro Trackball Compatible with Windows and macOS. - Brand: Kensington - Model Name: SlimBlade Pro Trackball - Color: Gray - Supported OS: Windows, macOS [Product] Kensington Slimblade Pro Wireless Trackball 4 buttons Symmetrical design 55mm ball Wired connection 2.4GHz wireless connection, Bluetooth connection Mac compatible K72085JP Power supply: Rechargeable Connection type: Wired/Wireless (Bluetooth) [Description] Three connection types to choose from: You can choose the connection type that best suits you with three connection types: Bluetooth, 2.4GHz wireless connection, and wired connection. Rechargeable included battery: You can charge the battery simply by connecting the included wire to USB-C. It can be charged for about 4 months of battery life. Precise operation with horizontal twist ball movement: You can easily scroll through websites and Word documents by twisting the ball horizontally. Symmetrical design for both right-handed and left-handed users: The low-profile design and symmetrical design are suitable for both right-handed and left-handed users. You can use it while reducing the burden on your hands and arms even during long hours of work. Operation with optical tracking technology: Equipped with dual sensors, it enables precise and accurate cursor tracking and scrolling.