Modern armor's goal is to provide versatile firepower that can operate in any battlefield condition, while at the same time ensuring the safety of its crew. Sophisticated electronics allows modern tanks to operate in any weather, day or night, with no significant performance degradation. Capable of nearly 50 mph in rugged terrain, these fighting vehicles are often in the 50-60 ton range. Though their firepower varies, most of these advanced tracked vehicles are equipped with 100mm+ cannons, in addition to other smaller caliber machine guns. Depending on the assignment, some versions include "reactive" armor, which helps to thwart the advanced armor-penetrating munitions seen on today's battlefields.