The Firefield .264 Win/ 7mm Rem Mag In-Chamber Red Laser Brass Boresight is a compact, ightweight boresight with a durable brass construction, perfect for hunting or target shooting. The Firefield in-chamber red laser brass boresights deliver precision accuracy without wasting time and ammo at the range. Once placed in the chamber of a firearm, the red laser dot appears exactly where the barrel is pointed, allowing the weapon sight to be adjusted to the theoretical impact point. It’s easy to attache it to the rifle to begin shooting in minutes and to pack and carry it wherever you go, from the range to the field.