What is "ichcahuipilli"

The ichcahuipilli (from Nahuatl: ichcatl, cotton, and huīpīlli, shirt)(known in Spanish as "Escaupil") was a Mesoamerican military armor, similar to the European gambeson, and was commonly used by the Aztecs and the Tlaxcalans. It was constructed of several layers of braided cotton at least 2 inches thick, and hardened with brine and other substances.