Get great results on your next hunt with the SSI Site-Rite .243 / 7mm-08 Chamber Cartridge Laser Boresighter, which features a precision-machined brass casing and a high-output laser to provide optimum accuracy. This boresighter is factory aligned to fit .243 Win, .308 Win and 7 - 8mm caliber firearms, and it includes 3 LR41 lithium batteries.