Firefield Ironclad Mini Reflex Sight - F1This red dot uses the Docter footprint standard. The Firefield Ironclad Mini Reflex Sight F1 is a compact powerhouse of a red dot optic, built tough for the rigors of shooting and making it the ultimate choice for pistols or backup setups. These red dot sights from Firefield are compatible with handguns featuring the Docter, Venom, or Fastfire footprints and are housed in a rugged, rubber coated aircraft grade aluminum casing that ensures durability