The Sightron S-TAC4-20X50 Rifle Scope features a magnification of 4-20x with an objective diameter of 50mm. This scope has a fast focus eyebell for quick and easy adjustments when in the field. The precision adjustable target turret adjusts in .25 MOA adjustments and are resettable to zero. It is protected by rugged windage and elevation caps. A pop up style zoom ring lever allows for ease of use in cold weather climates. This scope is waterproof, shockproof, and nitrogen gase charged.