Where Does The Knight Fit In And What Is The Role Of The Fustian Tunic?

The Canterbury Tales by Geoffrey Chauser is about 29 characters on a journey to a shrine for religious purposes. They each have to tell four stories. If they are able to tell the best story, then they’ll win a free feast. The Knight and his son, the Squire, were two of the characters going on that journey.
The Knight is a distinguished man. Furthermore, he was respected by everyone for his great deeds and Christian values. He had traveled around the world fighting for his kingdom, and he has always come out victorious. Because of his great status and class, he was able to purchase lots of horses that are strong and healthy. He is a large man with a gentle heart. Furthermore, he is strong and agile. The Knight is supposed to be a perfect character, therefore he does not have negative attributes like his son. He is a man with many virtues: such as truth, honor, generosity, chivalry, courtesy, noble, and wise man. He can also be seen as a simple man by the way he dresses. Chauser describes him as 'a true, a perfect gentle-knight', 'modest as a maid'. 'He wore a fustian tunic stained and dark/with smudges where his armor had left mark' The Knight wore fustian tunic (which is simple and plain) unlike his son who dressed to impress the women.