The Viridian RFX11 is an open-emitter micro reflex green dot for pistols, built on the Shield RMSc footprint. It mounts to RMSc-cut subcompact slides such as the S&W Shield, Sig P365, Springfield Hellcat, and Glock 43X/48 MOS. This unit is finished in FDE. Features: 3 MOA green dot Open-emitter reflex design Shield RMSc footprint Instant-On activation with automatic brightness adjustment CR2032 battery, up to ~30,000 hours runtime IPX4 water resistance Weighs ~0.56 oz FDE finish Confirm your slide is cut for the Shield RMSc footprint before ordering.