The Viper Red Dot's super-low mounting height makes it the perfect solution for handguns with cutout slides. The Viper gives shooters the simplicity and speed advantage of a dot sight, while co-witnessing with stock iron sights. The trade off? Nothing. The 6 MOA dot diameter gets shooters on target fast. Fully multi-coated, ultra-clear lens offers a wide, unobstructed field of view. The left-side up/down power and illumination controls are easy to access and manipulate. Recessed 1 MOA windage and elevation adjustments are super clean, protected from incidental contact, and always at the ready. It runs on a CR 2032 battery. The Viper comes with a Picatinny mount-weighs Mfg: Vortex Optics