Connect midle part to the rim using o-rings - adjust stiffness using different kind of o-rings. You can also place two aditional big o-rings around midle part to hold it firmly in place. It is designed for use with GoPro in water-proff case and will break on impact - keeping mounts and frame from breaking. So far I have around 5 hours of fly-time using it and 5 crashes - in 3 of 5 cases it broke on impact. Use at your own risk. PS: There is also a simple part which just replaces stock plate. You can also use it to create your own version of mount.Print using medium settings, without support.