tainless steel disk assists in affixing gyros onto your skewer. Just squeeze your meat in between two disks and they work as well as a prong/spike, only it’s easier to carve the meat because there aren’t any spikes to avoid.
If you are cooking any animal with a spine then a back brace is recommended. This goes through the back of the animal around the spine and holds the carcass to the skewer. This eliminates the animal bowing while cooking.