Features: - Fast Focus Eyebell: Featured with all SIII Series Riflescopes. Allows for quick and easy adjustments when in the field. Diopter adjustment ranges from -2.0 to +1.0 settings. - ExacTrack: This scope features Sightron's unique ExacTrack windage and elevation adjustment system. No other system on the market comes close to the precision and performance of ExacTrack. - All Weather Construction: This scope features the ultimate in all weather construction. They are waterproof, nitrogen filled and provide a lifetime of internal fog protection for inclement weather. - Tactical Turrets 0.1 MRAD: Exposed Large Tactical Style Turrets that are Offered in 0.1 MRAD adjustments. Torx 20 set screw positioned on top of turret allows for quick and easy adjustment when resetting back to zero. - ZACT-7 Revcoat Multi-Coating (S-TAC Series): All Sightron S-TAC 30mm Series Riflescopes feature ZACT-7 seven layer multi-coating with precision ground glass. These lenses provide superior light transmission and resolution for the ultimate in performance. - S-TAC One-Piece Main-Tube: All scopes in the S-TAC series feature a 30mm one-piece Main-Tube made from high quality Aircraft aluminum. Tube thickness is more than twice as thick as one inch models to provide maximum rigidity. All models are fogproof, shockproof and waterproof.