The Zero Tech Optics THDM21 Thrive HD Black 1x 21mm x 15mm 3 MOA Red Dot Reticle is a compact micro reflex sight built on the RMSc footprint for seamless mounting to most optics-ready pistols. Its open-emitter design, multi-coated lens, and crisp 3 MOA red dot provide a clear aiming point while maintaining an unobstructed field of view. Advanced shake-awake electronics, waterproof and shockproof construction, and a lightweight aluminum housing make it a dependable everyday companion on your slide or as an ultra-light backup sight on other platforms.

With unlimited eye relief and an unlimited field of view, the Thrive HD is well suited for fast target transitions at the range, competition use, and training-focused carry setups where rapid sight acquisition matters. Ten adjustable brightness settings and a long-life CR2032 power source keep the dot usable in a wide range of lighting conditions, from indoor bays to bright daylight. Thoughtful details like the moulded rubber cover, included mounting screws, and lens cloth reflect ZeroTech’s focus on practical design and consistent performance.

• Manufacturer: ZeroTech Optics
• Model: Thrive HD Micro Reflex THDM21
• Magnification: 1x
• Objective Lens Diameter: 21mm x 15mm
• Reticle: 3 MOA Red Dot
• Brightness Settings: 10 Adjustable Levels
• Battery: CR2032
• Battery Life: Up To 150,000 Hours
• Eye Relief: Unlimited
• Field of View: Unlimited
• Optic Footprint: RMSc
• Lens Coating: Fully Multi-Coated
• Length: 40mm
• Weight: Approximately 19 Grams
• What's In The Box: Optic, Rubber Cover, Lens Cloth, Hex Keys, Mounting Screws