This is a backer plate to support installation of a custom water cooler (or any kind of cooler) onto a LGA1366 socket motherboard. Creates a more rigid back plane around the socket when mounting your cooler.
There is even a mounting to support a low profile 40mm fan on the back of the socket.
Layer height: 0.2 - 0.26mm
I have two of these mounted to two Asus P6T-SE X58 motherboards supporting custom water blocks, cooling Xeon X5675 6 core processors. They are strong enough to allow you to apply correct pressure ensuring good Thermal Interface.
Hope this helps someone.