This bracket from Zipp enables you to mount a Garmin 800 in front of your stem instead of on it. The bracket is made by SRAM but has the Zipp log on it.

The clamp size is 22.3mm and the bracket is clamp is left of where the Garmin would mount.

Total length of the bracket is 80mm.

Please note: This bracket is designed to fit on Tri Bars so on a normal flat bar the device will sit horizontal rather than vertical.