Fits All Browning Bar & Long Action BLR & Benelli R1, Short Action BLR Models. Action: All Bar & Long Action BLR & Benelli R1. Precision machined from a solid block of top-grade billet 6061T6 aluminum Custom made to fit each type of firearm and align perfectly with your rifle receiver No moving parts between the firearm and the scope 67 percent lighter than comparable one-piece mounts with four times the threads and precision socket-head cap screws for absolute strength and security Absorbs shock and withstands temperature extremes better than steel mounts at a fraction of the weight Made in the USA Browning BAR and Long action BLR: All BAR actions use the same mount. This mount also fits the long action BLR. Base screws are 6-48 X 1/4" long and ring screws are 6-40 X 5/8". Both use 7/64 Allen wrench. Outside to outside of rings is 4.24". Rings are .63" wide. 4 Hole to hole spacing dimensions are .50", 3.19", .50". Height of mounts from top of receiver to centerline of scope tube is - low .94", medium 1.06", and high 1.19". Mount fits both left and right hand firearms. Same mount used on a Benelli R1 rifle.