Tired of buying a boresight for every caliber? Introducing Osprey’s Boresight Arbors. These arbors are made to fit our 223 Green Laser Boresight, which has a green laser (instead of red) and is very visible, even during daylight hours. Save time and money with our available arbors in 11 different calibers. They are backed by Osprey’s industry leading no-nonsense lifetime warranty.