The formal Thai national costume, known in Thai as ชุดไทยพระราชนิยม Chut Thai phra ratcha niyom, literally Thai dress of royal endorsement), includes several sets of clothing designed for use as national costume in formal occasions. (www.pompgorn.com) The men's national costume is known as suea phraratchathan เสื้อพระราชทาน. (Wikipedia)