Loc: S.A. and Kinney Co.
I have them on every Rem 700, 5 seekins bases. For one,consistency as well all wear seeking rings. My rim fire does not because seekins does not make a base for a CZ 455. And my AW has a Spuhr mount which has a lug
Any recoil lug on the base will help hold it in place from moving during firing. I like them. But, I have had some bases that had the recoil lugs, and caused the screw holes to be out of center, so one or both of the measurements were off. I could not get the base to work because of the recoil lugs. But when they work, I like them.