to offer three protection classes which are wholly or partly interchangeable. Protection class A is the basic vehicle, at 31.5 metric tons combat-ready weight air transportable in the A400M. Protection class C consists of two large side panels that cover almost the whole flanks of the vehicle and act as skirts to the tracks, a near-complete turret cover and armor plates for most of the vehicle's roof. The side panels are a mix of composite and spaced armor. It adds about 9 metric tons to the gross weight. Originally, there was also a protection class B designed for transport by rail. However, it became obvious that class C lies within the weight and dimension limits for train/ship transportation, thus class B was scrapped. The Puma is protected by AMAP composite armor, the AMAP-B module is used for protection against kinetic energy threats, while AMAP-SC offers protection against shaped charges. A group of four A400M aircraft could fly three class A Pumas into a theatre, with the fourth airplane transporting the class C armor kits and simple lifting equipment. The Pumas could be built-up to armor class C within a short time. The basic armor can resist direct hits from 14.5 mm Russian rounds, the most powerful HMG cartridge in common use today (and up to twice as powerful as the western de facto standard 12.7 mm .50 BMG cartridge). The frontal armor offers protection against medium caliber projectiles and shaped charge projectiles. In protection class C, the flanks of the Puma are up-armored to about the same level of protection as is the front, while the roof armor is able to withstand artillery or mortar bomblets. The Pumas of the German Army will be equipped with a soft-kill system called Multifunktionales Selbstschutz-System (multifunction self protection system), MUSS, which is capable of defeating ATGMs. The whole vehicle is protected against heavy blast mines (up to 10 kg) and projectile charges from below, while still retaining 450 mm ground clearance. Almost all equipment within the cabin, including the seats, has no direct contact to the floor, which adds to crew and technical safety. All cabin roof hatches are of the side-slide type, which make them easier to open manually, even when they are obstructed by debris. The exhaust is mixed with fresh air and vented at the rear left side. Together with a special IR-suppressing paint, this aims at reducing the thermal