Sig optics red dot romeo msr 1x20 2 moa m1913 compact blk< FEATURES:Reticle: 2 MOA Red DotIllumination setting: 10 daytime/2 NVSlip over see through flip backsTop loading battery compartmentLength: 7.2Width: 11.0Height: 2.2 Other Features: Ultra compact size and weight, unlimited eye relief,parallax free,slip over see-through flip backs,top loading battery compartment 20,000 hour run time on cr223 battery,ipx-7 waterproof and fogproof performance,10 daytime settings and 2 nv settings