The basic armor of the Mongol fighting man consisted of a heavy coat fastened at the waist by a leather belt. From the belt would hang his sword, dagger, and possibly an axe. This long robe-like coat would double over, left breast over right, and be secured with a button a few inches below the right armpit. The coat was lined with fur. Underneath the coat, a shirt-like undergarment with long, wide sleeves was commonly worn. Silk and metallic thread were increasingly used. The Mongols wore protective heavy silk undershirts. Even if an arrow pierced their mail or leather outer garment, the silk from the undershirt would stretch to wrap itself around the arrow as it entered the body, reducing damage caused by the arrow shaft, and making removal of the arrow easier.