Ultimate Arms Gear Tactical QD Quick Detach CQB Tactical 4 Reticle Dual Red/Green Open Reflex Sight with Weaver-Picatinny Rail Mount Tubeless Open Reflex Design 4 Separate Reticle Patterns In Both Red and Green 6 Diferent Brightness Settings (3-Red 3-Green) Weaver-Picatinny Rail Base With Innovative Quick Release Lever For Secure Rapid Mounting / Dismounting Windage and elevation adjustments