The M136 AT-4 is a lightweight, multipurpose weapon. Unlike the M72A2 LAW, it doesn't need to be extended to fire. The AT-4 is issued as a round of ammunition. It comes with a disposable fiberglass launcher and an 84-mm HE shaped charge capable of penetrating 15.7 inches of homogenous armor. The AT-4 has pop-up sights for day use, and a night sight can also be attached.