Aimshot Modular Features The AimShot Modular bore sight is chambered specifically for 9mm Luger inserting into the chamber to project a visible 650nm red laser down the bore for fast repeatable zeroing. This lets shooters confirm or adjust their optic s point of impact without expending ammunition saving both time and money at the range. The modular design is what sets this bore sight apart allowing the small internal watch batteries and end cap to be removed in favor of an external battery solution. This flexibility gives shooters options depending on how long a zeroing session is expected to take. Included with the kit is an external battery pack that houses 2 AAA batteries extending run time to over 20 hours far beyond what the small internal batteries alone can provide. A small magnet built into the external pack holds it securely against the firearm s receiver keeping the setup stable and in place while shooters take the time needed to properly dial in their optics. Both the internal watch batteries and the AAA batteries for the external pack are included with the kit. This combination of extended battery life and modular design makes the AimShot Modular bore sight a practical flexible tool for 9mm Luger shooters. Aimshot Modular Specifications Manufacturer: AimShot Model: Modular Caliber: 9mm Luger Laser Color: Red Wavelength: 650nM Battery Life: 20+hrs Battery Size: L736 Includes: Batteries Available At: GrabAGun