Aircraft-grade aluminum adapter rail lets you use Picatinny scope 3/8" or European 11mm dovetail mounts found on many bolt-action rimfire rifles. Six crossbolts apply even pressure along length of dovetail to keep the adapter rail centered. Generous cross slots give you increased scope ring and optics choices, whether for weekend plinking or informal competition. Perfect for mounting a red dog sight. Clamping screws also fit into pre-drilled holes to equally spread the legs so you can easily slip the mount onto oversized rails. Extends approximately .620" above dovetail. 4" single rail weighs 3.1 oz. (g). Two 1" rail sections weigh .75 oz. (g) each. Hardcoat anodized, mat Mfg: Bkl Technologies