The ZERO TECH OPTICS THDMM21 Thrive HD Multi Reticle Red Micro Reflex Sight is an exceptionally lightweight and slim line optic designed for superior target acquisition, offering a 1x magnification and a compact 21mm x 15mm objective that keeps the sight profile low without sacrificing light gathering. Engineered with advanced shake awake technology, this micro reflex sight powers up quickly as soon as motion is detected, helping you maintain fast follow-up shots in dynamic shooting scenarios. The multi-reticle system provides flexible aiming options, allowing you to tailor the reticle to different targets and engagement distances, which enhances acquisition speed and improves re-engagement after recoil. Built for rugged use, the Thrive HD is fog, shock, and waterproof, ensuring reliability across varying conditions. It is designed for Picatinny mounts, enabling secure attachment to a wide range of platforms, while remaining compatible with firearms that require no magnification for quick close-quarters encounters or sport shooting. Included with the sight are a rubber protective cover, a microfiber lens cleaning cloth, hex keys for sight attachment, and three sets of mounting screws to suit different rail configurations, delivering a complete, ready-to-use optical solution.