Handguns. Shotguns. Offset on a carbine. Whether running drills at the range or holding the line during rigorous duty use, the Defender-ST(TM) is ready when and wherever you are. Rugged and reliable? It's a given. Large sight window? Absolutely. Motion- activation and a dot with adjustable brightness deliver superior target acquisition, adaptability in all lighting conditions, Defender-ST(TM), you're not just range-ready, but armored for the toughness and adaptability your world demands. 3 MOA DOT Reticle - The Vortex Defender-ST(TM) features a total of 12 brightness settings (ten for daylight use and two for night vision). Offered with a 3 MOA daylight bright green dot, it is easy to see and acquire targets regardless of lighting conditions or background. FEATURES : Bright Green Dot - Targets quickly in varied lighting and diverse backgrounds ShockShield(TM) Polymer Insert - To protect against hard, daily abuse Textured Grip - Aggressive texturing on face of optic for racking slide off any surface Button Lockout - Prevents accidental brightness adjustment during use or transport. Low-Glare Matte Black Anodized - Corrosion and wear resistant anodization provides low-glare matte surface and helps camouflage the shooter's position 10 Daylight brightness settings - illuminated center dot aids in faster center-point acquisition in bright daylight conditions Parallax Free - All green dots and holographic sights will exhibit some small amount of parallax. Matching current industry practice, this small amount would be considered "parallax free" and will make a negligible difference in performance.