Where is Muay thai native to ?
( 64.59 kg - 66.8 kg ) World Muay Thai Council ( WMC ) , welterweight range is from 140 pounds ( 63.5 kg ) to 147 pounds ( 66.6 kg ) World Muay Thai Federation ( WMF ) , the official amateur organization , fixed welterweight from 63.5 to 67 kg for adult ; the Junior category is the same as adult