Firefield Ironclad Mini Reflex Sight - F3This red dot uses the Shield RMSc footprint standard. The Firefield Ironclad Mini Reflex Sight F3 is a compact and highly versatile red dot optic designed for extreme durability and lightning fast target acquisition on pistols and backup setups. These Red Dot Sights from Firefield are compatible with handguns featuring the RMSc footprint and are housed in a rugged, rubber coated 6061 aluminum casing that is both shockproof and fogproof to handle heavy