There is nothing quite like it on the market. It costs about a million dollars, comes in a handy package and outshoots most if not all its rivals.
For the South African manufacturer, Armscor, the role of the 155mm gun on both sides in the eight-year Iran-Iraq war has added credibility to its claim - emblazoned across full-page advertisements in international defense magazines - to provide customers with fully combat-tested equipment."The G-5 has an extremely strong design," said Henry Dodds of Defense Marketing Services, London. "Using extended-range, full-bore ammunition the G-5 has a range of 39 km (24 miles) - better than anything else around."
The Soviet equivalent, the D-20, has a range of 15 miles, while NATO's FH-70 can reach out to 20 miles.
Artillery has long played a special role on the battlefield.
While infantry seize and hold ground and armored forces maneuver to deliver the decisive blow, the big guns keep an opponent off balance, pin him down and commit his forces to battle before he is ready to fight.
"If you've been under artillery fire, you'll know how disconcerting it is, especially in the open," said one soldier. "Even if you are well dug-in, it'll bring tears to your eyes."
For Iraqi as well as Iranian troops, analysts said, firepower was crucial to breaking up enemy forces as they moved in to attack. One specialist said so much ammunition was used that the bore in many artillery barrels wore thin.
The G-5 is more durable than most, and also very accurate.
"It's exceptional," said Christopher Foss, military editor of Jane's Defense Weekly. "At high elevation, it can fire a shell 40 km (25 miles). By using base bleed ammunition - in which a little powder is burnt in the base of the projectile as it leaves the barrel - the shell is steadier on its way to the target."
The South Africans, unlike their competitors, offer a package that includes the gun, a tractor to give it mobility and a fire control system.
Armscor will also provide the extended range ammunition.
Iraq is believed to have had the G-5 for at least three years, using it together with 200 of the French self-propelled, automatically loaded GCT 155mm howitzers as the backbone of its artillery regiments.
Iraq fields 3,500 guns and heavy mortars to Iran's 1,000.
Both Iran and Iraq acquired large numbers of the Austrian GHN-45 gun, one of the G-5's several ancestors. But analysts say Baghdad was not entirely happy with it, and approached South Africa for 155mm ammunition. The G-5 soon followed.