The Weaver Quad Lock Detachable Rings will hold zero as securely and as strongly as your fixed mounts would. But they also enable your scope to swing off to either side. When the rings are closed, the sturdy spring will lock them into place with a latch and bring you back to zero. These rings feature two straps and four screws for added gripping power for these lightweight, all aircraft aluminum rings. Weaver legendary quality at a modest price. Extension allows you to adjust your scope front or back for a custom fit.