I currently live in Thailand and there is really only 1 brand that's used (If there is another brand I've never seen anyone use it!) nationwide by all the street vendors to make traditional Thai Ice Tea and that's this one...

![enter image description here][1]


  [1]: https://i.sstatic.net/bMgtE.jpg

I don't know the name of it but I'm pretty sure it's just Number One Brand. I'll confirm the name when I get chance!