The latest AimShot 223 20x modular laser bore sight with Modular Battery Pack. This version of our proven 223 laser bore sight adds the modular battery pack that allows you to remove the small watch batteries and end cap (included) and replace with it with an external battery pack that contains 2 AAA batteries (included) that will give you run times of 20+ hours for your laser bore sight. The 20X designation is for the brighter red laser that is easier to see over long distances or in full sunlight. 632nm wavelength red laser is more visible to the human eye and is brighter. The latest modular bore sight includes BOTH the smaller watch batteries and end cap, as well as the latest external battery pack that runs on 2 AAA batteries for 20+ hours of laser run time. The external battery pack has a small magnet on the side to hold it to the receiver and allow you extra time to get your optics dialed in and a small switch on the back of the battery case that allows you to turn the unit on and off easily.
 
AimShot always recommends removing the bolt or locking it back solidly to prevent accidental closure and breaking the wire or bore sight. But if this happens you can purchase a new MBP223 and be up and running quickly and easily and not even have to send the unit back to AimShot for repair. This the laser that AimShot recommends use with any of our rifle arbors for bore sighting other rifle calibers.
 
The AimShot laser bore sight system is designed around a single high quality laser, 223 for the rifle calibers, and a system of hollow arbors that are designed to fit over the 223 laser and fit in the chamber for other calibers. So if you want to bore sight a 308, you would need the 223 laser and then the appropriate arbor (AR243 in this case will fit all 308 based calibers). Being able to bore sight additional calibers by purchasing an arbor is much more cost effective.
 
It is the most versitile and accurate system on the market, and should not be compared to any other chamber based bore sights. AimShot has the original patent on the chamber laser bore sight and still makes the best system. More accurate, more durable, longer lasting and functionally superior to any other system on the market. Used extensively by manufacturers in the industry, and the US military. The original and still the best. 
<5mW FDA Class IIIa laser