This is a bracket for mounting an Antec AIO watercooling system (in this case, Antec H950 pro) on a GTX 1080ti founders edition.
From my research, this should fit most founder edition cards from most generations. This was tested only on the 1080ti FE.
I used 5mmx5mm M3 knurled nuts and M3 bolts and washers.
To read more about the project and to see more photos, please visit : https://harariprojects.com/2018/10/29/water-cooling-a-gtx-1080ti/