Surefire updates the X300 Ultra Weaponlight, giving it a boost of 600 lumens for the Surefire X300 Ultra-B Weaponlight... "The powerful, virtually indestructible X300 Ultra WeaponLight was primarily designed for handguns but is also excellent for long guns and mounts securely to MIL-STD 1913 rail-equipped rifles via its newly enhanced T-slot mounting system.