MUAY THAI RANKING SYSTEM
Traditionally Muay Thai grading was not structured as it is today. A Kru would recognize those skilled in the art by bestowing on them blessed Prajeat/Kuang Rang (armbands) and Mongkol (headband), historically the arm band was presented to warriors on the battle field by their Masters. The modern day fighter still wears the arm band usually presented to him by his Grand Master, Master or Kru.
The Mongkol Ranking System for Sityodtong Headquarters in Boston
White - Basic
Blue - Advanced
Purple - Apprentice Instructor
Red - Associates Degree Instructor
Gold - Master