Fyland Tactical Red Dot Sight 4 Reticles Green and Red Reflex Sight for Rifle Gun with Weaver Picatinny Rail Mount Fully multi-coated lens offers a clear and wide field of view for fast target aquisition Reflex sight offers four adjustable reticle patterns and multiple brightness settings Top mounted battery compartment makes it quick and easy to replace the battery Red/Green dot sight is compatible with a 20 mm weaver or picatinny rail Features a strong aluminum body construction for durability.Battery and protective cover are included