The YW-531a was the first APC manufactured by Norinco for the PLA. It was designed in the early 1960’s and first appeared in 1964. It can carry a crew of 4 to 10 troops. The YW-531 was first used in the Vietnam War by the North Vietnamese Army (PAVN) and was in action again in the Iran-Iraq War.
APCs are usually armed with only a machine gun although variants carry recoilless rifles, anti-tank guided missiles (ATGMs), or mortars. They are not usually designed to take part in a direct-fire battle, but to carry troops to the battlefield safe from shrapnel and ambush. Amor on APCs is usually composed of simple steel or aluminum, sufficient for protection against small fire arms and most shell fragments. Just about any type of anti-tank weapon can defeat the armor of an APC. Some APCs also come with NBC protection, which would protect its crew from radioactive fallout or the like.