The Primary Arms Micro Dot with Fixed Base GEN II is a great choice when you need a Micro dot mounted as low as possible on a 1913 Picatinny rail. The low profile emitter is offset to the right, allowing use of iron sights with many host firearms. The MD-FBG II features 1,000 hours of battery life from the included CR2032 battery at a medium setting and an ultra-sharp 2 MOA dot. The brightness knob above the tube adjusts 12 brightness settings from night vision compatible to daylight bright. This tough optic is waterproof, with a 1 year warranty. Rubber “bikini” lens cover included.