Saenchai won the Lumpinee Stadium title, which is widely considered the most prestigious title in Muay Thai, in four different weight divisions, while mostly fighting larger opponents.
Traditional Muay Thai does not have a ranking system, which means that it does not have belts eithers. Fighters do wear traditional armbands called praciat or prajead but they don't symbolise a rank, they're just symbolic pieces of equipment and nothing more.