AFAIK

Thai nationals only (must have a Thai ID card).

Discount is quite small, on the order of 5% or less.

Good only on TG domestic flights, only on certain days of the week (Tuesdays for sure).

Limited to certain economy fare classes.


but I haven't checked into this in 1 + year. Any travel agent should be able to confirm the details

Speaking of notorious double and triple pricing schemes, what's up with these different prices for children and seniors in the U.S.?