The Leupold Open Range Rimfire 3/8" 1-piece base is a lightweight and dependable mounting solution for rimfire rifles equipped with 11mm or 3/8-inch dovetail rails. Precision-machined from high-grade aluminum, this base provides a no-tap installation method and is compatible with riflescopes featuring a 1-inch maintube. Designed as a high-quality alternative to manufacturer ringmounts, it offers secure, stable scope mounting while maintaining a low-profile footprint.