The name of the war banner (vexillum belli) flown by the Knights Templar in the 12th and 13th centuries was Baucent (bauceant, baussant, etc.). Sources from the 13th century depict it as a white gonfanon with a black chief (argent a chief sable). The gonfanon baucent is mentioned by Jacques de Vitry in a book from the 1220s. He adds that the black and white colors stand for the Templars' aggressiveness toward their adversaries and their benevolence among their allies. The crimson Templar cross might have been added to the banner later in the 13th century, according to appearances.
Each squadron (eschielle) of the order had its own banner, according to the laws of the order as published by Münter (1794). Five to 10 brothers were especially tasked with guarding the banner since the banner-bearer had to keep a safe distance from the adversary during battle. Any brother who became separated from his banner was required to make an effort to find the closest Christian flag in the field. As long as at least one banner of the order was still flying, no brother was allowed to leave the field of battle without risking expulsion from the order. The troops were supposed to swarm to the Hospitallers' or any other remaining Christian flag if all of the Templars' banners were destroyed. They were only allowed to consider their own safety when the last Christian banner had fallen.
At Medieval Armoury, we try to replicate the originals designs as adding new templar designs to the banners. We have from the simpliest of templar banners to high decorative of the modern Templar Organization. Carry your templar banner with you and make your enemies see you coming with your sword held high.