The version of the M-2 Bradley fighting vehicle that the United States is donating to Ukraine isn’t the latest version. No, it’s the variant of the tracked, 25-ton vehicle the U.S. Army developed in the aftermath of the 1991 Operation Desert Storm.

The M-2A2 ODS by now is a 30-year-old vehicle. But its age belies its effectiveness. The three-person M-2 is an infantry fighting vehicle whose job it is to haul a six-person infantry team into battle, protect the infantry as they dismount then support them with the vehicle’s 25-millimeter autocannon and anti-tank missiles.

The latter are key. Yes, the M-2 is a battle-taxi with much thinner armor than any tank. But it’s a tank-killing battle-taxi. “The Bradley specifically has formidable anti-armor capabilities that will work against, you know, every kind of armored capability that Russia has fielded in Ukraine,” Laura Cooper, a deputy assistant secretary of defense, told reporters on Friday.

The U.S. Army and vehicle-maker United Defense, later BAE Systems, developed the M-2 in the 1960s. Mechanized armies decades earlier had learned that tanks, while fast and hard-hitting, are vulnerable to infantry ambushing them from the sides and behind. Tanks need friendly infantry to protect them from enemy infantry. But the friendly infantry need some way to keep up with the speedy tanks and safely deploy in the middle of a firefight.

The German army was first to solve this problem, with the HS.30—an infantry-carrying armored vehicle with a rear ramp and a turret-mounted heavy gun that made its debut in the late 1950s. The Marder, a much-improved IFV, quickly replaced the HS.30 in German service. The Soviet army meanwhile was fielding the first generation of its own IFV, the BMP.

The Americans lagged far behind in mechanized infantry technology. The Bradley was the U.S. Army’s first true IFV, and it didn’t enter service until 1981—nearly 25 years after the HS.30 first appeared.

The Americans worked hard to catch up. The M-2 was still a young design when the United States and its allies went to war with Iraq in 1991. At the Battle of 73 Easting in southern Iraq on Feb. 26, the U.S. Army’s 2nd Armored Cavalry Regiment, with a hundred M-2s and a hundred M-1 tanks, dismantled two Iraqi army brigades.

The Iraqis lost around 400 vehicles and as many as a thousand soldiers killed. The 2nd ACR lost one Bradley and six soldiers killed.

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The M-2s in the course of the battle fired more than a hundred TOW anti-tank missiles from their turret-mounted twin launchers—to devastating effect. Gary Bloedorn, an analyst with the Institute for Defense Analyses, described the Bradley’s advantages in a 1992 study of 73 Easting.

Early in the battle, the 2nd ACR’s Bradleys with their long-range optics spotted Iraqi MTLB scout vehicles many hundreds of yards away. The M-2’s height—10 feet from the bottom of the tracks to the top of the turret—actually helped crews surveil targets. “Keep in mind the Bradley fighting vehicle’s ‘doghouse’ for its thermal sight is about 13 inches higher than the M-1’s,” Bloedorn said. “So the Bradleys could see these MTLBs through this stuff at longer ranges and pick them up quicker, and the TOW missiles were dead reliable. When they fired the TOWs, they went where they shot them.”

One of the lessons the U.S. Army took from the 1991 war was that the M-2, even in its least mature form, was a highly capable anti-armor platform. “The Brad … is not a tank, but it can be a tank-killer,” tweeted Mark Hertling, a retired U.S. Army general who commanded an M-3, a scout version of the M-2, in Desert Storm.

The M-2 can fire its 50-pound, wire-guided TOW missiles out to a distance of two miles. “The anti-tank missiles have a longer range than the [Russian] tank cannon,” Hertling pointed out. With careful tactics, M-2 crews can maneuver around enemy tanks, jabbing at them with TOWs while staying just outside the reach of the enemy’s own weapons.

After the ‘91 war, the Army upgraded its thousands of M-2s to the new M-2A2 ODS standard, which added a laser rangefinder and GPS and boosted the vehicle’s anti-tank firepower by installing racks for Javelin anti-tank missiles, which in weight and range are similar to TOWs. Now an M-2 crew and its dismounted infantry team both could shoot missiles at enemy tanks from beyond the range of the tanks’ main guns.

Today the U.S. Army mostly uses M-2A3 and M-2A4 Bradleys with additional armor, engine and sensor upgrades. The older M-2A2 ODSs, as many as 2,000 of them, went into storage. It’s those ODS-models that are going to Ukraine.

The first package includes 50 M-2s, 500 TOW missiles and 250,000 rounds of 25-millimeter ammunition. And training for Ukrainian crews, of course. “The Bradley vehicles will further enhance Ukraine’s ability to conduct complex maneuvers in almost all weather conditions and terrain, especially in the south and the east of the country,” Cooper said.

And they’ll add “significant anti-armor capability” to whatever brigades they re-equip.