This will update your firmware. 

Download For The Short Dongle (.75in)

Download Firmware

Download For The Long Dongle (1.31in)

Download Firmware

The Mouse firmware can be updated via a phone.

1. Install nRF Connect on your phone.
2. Download firmware and save it to your phone. You can use iCloud Drive or Google Drive etc, to transfer to your phone. Do not unpack the firmware zip file.
3. Open nRF Connect.
4. Set mouse to Bluetooth and press the pairing button on the bottom of the mouse.
5. Press the scan button on nRF Connect.
6. Connect to Bluetooth EXOvault in nRF Connect.
7. A pairing confrontation dialog will appear select Pair.
8. Slide to the right to the third window.
9. Open the document Picker and find and select the
10. Press start. You will see the code being transferred. I will take less than 30 seconds to update. The software will announce, "Your DFU update was completed successfully" when done.
11. You have updated the firmware. You can close nRF Connect.