Hope it compensates for the hole or holes drilled off of center. Those Millet rings have a lot of adjustment.All right, we have mounted the new bases. Fit is good. I had a set of spare nice Weaver low profile rings. I put everything together. It looked good, till I bore sighted it. Same problem! So, we have determined it is miss drilled a bit. I am getting the Millet adjustable rings today!