Anschutz discontinued their 4760-U1a/1 buttplate carrier. This one is a compatible item, re-designed it to give you a much better fit in the shoulder.
Now you can add a couple of buttplates to your old wood-stocked Anschutz rifle and swap them out quickly and easily. There is no threaded rod in the center for the thumbwheel. Just slide this one in, make a note of which mark the depth is set to, and lock it down.
You can also purchase a “Stop Collar” for this carrier