An M30 rocket is an extended-range, aerodynamically controlled, inertial and GPS guided munition fired by the M270 Multiple Launch Rocket System (MLRS). Properly, they are guided missiles rather than unguided rockets, but, since it is derived from the unguided M26, the U.S. Army has chosen to continue the "rocket" name.
It carries 404 of the same type of cluster submunition as the M26, the M85 DPICM but to a longer range of 37mi/60km. Both the M85, and the earlier M77 DPICM bomblets, have an unacceptable "dud" rate (i.e., failure to detonate on contact), while remaining highly explosive. The duds effectively create an antipersonnel minefield, in violation of the Ottawa Treaty and a political liability.