The Colt Law Enforcement Carbine LE6920 is a rifle that features many of the advantages of the military M4 comes equipped with a Magpul MBUS backup sight. It has a 16" barrel (as opposed to the M4A1's 14.5") with step-cuts to attach a launcher such as an M203 grenade launcher and the Cobray 37mm Launcher. In films, this gun has been converted to full auto to trick viewers into believing it is an M4A1, earning it the nickname "M4gery".
It was a firearm that a bank robber was using to hold up the bank with two other bank robbers in the Pilot episode of Lethal Weapon.