Middle Frame Bezel
The Middle frame is a piece of metal that holds all the components of the iPod together, it is essentially the chassis of the iPod. If it gets cracked or broken this is the part you need.
To install, simply remove all the iPod’s components from the old frame, and reinstall them around the replacement one.
The frame you receive may have already been used, but it will have been thoroughly checked for any signs of damage.