The ones we use in Texas at the ranch we hunt the guy has a 2 inch piece of pipe buried in the ground with concrete around it and another piece over the stub up coming out of the ground. It has a winch welded to it and pulley about 10 ft high. His will swivel so you can back a truck or side by side under it and hook to the deer and just spin the deer out of the truck without having to move the vehicle. It’s very simple. I don’t have any pictures of them but his are pretty cool