Maxima Grooved Receiver Line of scope mounts are designed to fill the need of mounting scopes to rifles with an integrated receiver mounting rail. Because each manufacturer has their own proprietary mounting rail design, each ring model must be machined to exacting tolerances for proper fit and function. The Maxima Grooved Receiver line fulfills that need. The precision CNC machined Warne rings provide unsurpassed strength, durability and quality, and fit a variety of rifle models including Ruger #1, Ruger 77, Mini 14 & 30, and Ruger Blackhawk and Redhawk. Maxima Fixed Rings are designed to be the strongest, most durable fixed mount system available. Typical steel scope mounts in th Mfg: Warne Mfg. Company SPECS: MIM Steel. Powder coat, Gloss black (Reg) or Matte black (Mat) in 1" (25.4mm) or 30mm (1.2") dia. Heights measured from top of base to inside bottom of ring. Medium: .460" (11.7mm). High: .585" (14.9mm).