For sale is one fully operational Kensington Expert Mouse - Wireless Ergonomic TrackBall Mouse. The trackball is fully working via Bluetooth, however, I have lost the 2.4GHz USB receiver dongle that allows you to connect via 2.4GHz wireless instead of Bluetooth wireless. You just have to download the software from the Kensington website on a Bluetooth capable computer to get the device working. I'm sure it works without the Kensington software, but best to get this anyway to give the ability to change the trackballs button configuration or scroll sensitivity to your own liking. Only one black unit with red trackball included in this sale. There is no palm rest or 2.4GHz USB dongle included.
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