 Use of L numbers starts in the 1950s and an equivalent system for military vehicles is the FV series (fighting vehicle).On occasion, the number following the letter designation corresponds to the year that the item was adopted; for example, the rifle variant of the SA80 was first adopted in 1985 and was designated as the ""L85A1 5.56mm Rifle"".Some weapons such as the M16A2 rifle, M18A1 Anti-Personnel Mine, M79 grenade launcher and M6-895 and M6-640 mortars were not given L numbers and are referred to in official documentation by their manufacturer's designations instead.