In early September 1997, it was reported that Iran had successfully tested a locally built rapid fire mobile field gun known as Raad-2 (Thunder-2).

[4] The Iranian Defense Industries Organization claimed that the 155 mm HM44 howitzer manufactured by the Hadid facility of the Iranian Defense Industries Organization had a high firing rate and accuracy.

[6] The gun's range was reported as 30 km (19 mi), and it also includes features such as a laser range-finder and a semi-automatic loading system.

The gun looks exactly like 155mm/39-cal M185 gun from M109A1 and is fitted with a double baffle muzzle brake, fume extractor, screw breech mechanism, hydro-pneumatic recuperator and a hydraulic recoil brake.

[4] The Raad-2 is crewed by 5 persons, with the driver stationed at the left with the power pack at the right.