The Bushnell .17 - .45 Caliber Expandable Arbor Kit Case and Arbors 743333 is an essential tool for quickly adjusting scope or iron sights to align with the rifle or handgun barrel. This professional boresighter kit includes a graduated grid sighting reticle, three expandable arbors, and a carry case. The arbors cover all calibers from .22 to .45, ensuring compatibility with a wide range of firearms. The compact design and durable construction make it a reliable choice for hunters and shooters seeking precise sighting adjustments