Open, or “exposed” reflex red dot sights are often battery operated and reflect their LED onto a single glass lens, ruggedly contained in a window with reinforced housing available on some models for added protection.

These sights allow virtually infinite eye relief and the single lens gives you the ability to acquire the red dot at a very wide angle of view. One of the potential downsides of sights like these is that they can be fragile if dropped or struck in exactly the wrong way.

Additionally, open-style sights leave the LED emitter open to being obstructed by dirt or debris, which would cause the optic to be totally unusable.

To combat the potential downsides of LED emitter-powered open style red dot sights, some manufacturers have designed versions that don’t need batteries.

replacing them with fiber-optics and Tritium. These versions use ambient light when available to power the reticle, and tritium in low-light conditions. If you never want to worry about batteries going out on you, this type of open red dot sight is a great choice. Let’s take a look at some of the most popular open-style red dot sights from top optics manufacturers.

• Sig Sauer Romero 1 Reflex sight with 6 MOA Red Dot

• Trijicon RMR Type 2 with 3.25 MOA Red Dot

• Nikon P-TACTICAL Spur with 3 MOA Red Dot

• Vortex Viper with 6 MOA Red Dot

• Vortex Razor with 3 MOA Red Dot

• Burris FastFire with 3 MOA Red Dot

• Leupold DeltaPoint Pro with 2.5 MOA Red Dot



Tube-style red dot sights

Red dot sights with tube assemblies are more durable than the open-style sights but the tradeoff comes with more weight and a larger footprint on your firearm than the open-style.

Functionally, this style of red dot works the same as most open style sights do, using an LED emitter. The LED is placed at the rear of the housing, reflects off the objective lens of the assembly and back to your eye.