M2 is American IFV. IFV is short for infantry fighting vehicle.
The newest version of M2 is M2A3. It has a 25 mm gun, a 7.62 mm gun and two anti-tank missile launchers.
It has a 600 hp diesel. It can transport six soldiers for once.
The M2A3 is a very good IFV. US Army has a lot of M2A3's. One infantry company has 14 M2A3's. One infantry platoon has 4 M2A3's.
The 25 mm gun of the M2A3 is called M242 Bushmaster. It's a chain gun. Its rate of fire is 200 rpm.