Precision machined from solid steel bar stock to exacting tolerances, these MAX-TAC Series rings and bases are equal to any on the market in precision and finish. All rings are 30mm with 1-inch inserts included. The rings fit Picatinny (Mil Std 1913) rail and weaver type bases. The bases are machined to the original weaver type dimensions so they will accept either Picatinny or standard weaver rings. All bases have either flat or 20 minute angle built in.