This DNZ Scope Mount - Browning BAR and LA BLR, 1" will also fit the long-action BAR line. Base screws are 6-48 X 1/4 inch long, and the rings screws are 6-40 X 5/8 inch. These screws all require the use of a 7/16 Allen wrench. The outside of the rings are 4.24 inches. This mount is made to fit both right- and left-hand guns. This mount is made from high-grade aluminum to withstand shock and the elements better than steel mounts.