The Sightron SIISS45X45EDTD Rifle Scope features a magnification of 45X with an objective diamter of 45mm and tube diameter of 30mm. Precision adjustable turrets are offered in .1 MOA adjustments and are resettable to zero and are protected by rugged windage and elevation caps. The side focus features parallax adjustment aimed for quick and easy adjustment and will focus from 10 yards focusing distance to infinity. The ExacTrack windage and elevation system applies proper alignment between the adjustments and the errector tube. The ED glass prevents chromatic aberration and the Zact-7 Revcoat employs revolutionary lens coating technology featuring fully multi-coated precision ground glass. This rifle scope is waterproof, shockproof, and nitrogen gas charged.