These units were supported by new volks-werfer brigades: artillery units firing masses of 150 mm and 300 mm rockets. Although lacking in accuracy, a barrage from these units could cover a large area with high explosive. For more infantry firepower, SS "Panzergrenadiers" were equipped with the new "Sturmgewehr" 44. This was the world's first mass-produced assault rifle and more advanced than any other military rifle at the time. The new "Panzerfaust" 100 was an improved short range anti-tank rocket grenade that could penetrate any armor fielded by the American army.