Logitech Wireless MX ERGO Color: Graphite Connectivity Technology: Bluetooth Special Feature: Trackball Missing Items: Receiver, charging cable Movement Detection Technology: Optical Number of Buttons: 8 There are no noticeable scratches. Trackball mice suit different people. Even among trackball mice, the feel of this mouse differs from others. In particular, the good point of this product is that the tilt angle can be adjusted to 20 degrees. This adjustment has made my shoulder and wrist more comfortable. I recommend this product for those who are using it for the first time. This is a high-performance trackball mouse from the Logitech MX series, which is designed to reduce fatigue in the arms and wrists. Since you move the trackball and not the body of the mouse to operate the cursor, it can be used in a space-saving manner. The tilt angle can be adjusted to 20°, allowing you to use the mouse in a more natural hand position, reducing muscle tension by 20% compared to a regular mouse. There is a precision mode button that allows you to change the tracking speed, and you can instantly switch between speed mode and precision mode with the push of a button. It is equipped with a tilt precision scroll wheel that allows for horizontal scrolling, middle click, and left/right tilt (sideways tilt). The Easy-switch function allows you to easily switch between up to 2 connected devices with the push of a button, allowing you to switch devices without stress. Connectivity: Compatible with Bluetooth or Unifying USB *Please note that this is not a silent type. *Please be aware that this is a used item. #Logicool #mx ergo #Logitech #Fast charging #Compatible with Windows, Mac, and iPad OS #Domestic genuine product