Press and shake, boost up, it is another new product of Thailand. It can be found out in front of every refrigerator in 7-11 Thailand. It is a cap, the ingredient contain inside the cap, you just need to get a bottle of drinking water and replace it with the cap, then tight it, and press the top, the powder will drop into the water and you can see the color of the water changing.
The green favor always sold out, so I tried the blue color today, the taste is good and it is not sweet, because it is sugar free, the taste like energy drink like glucose drink.
You should try it when you visit Thailand next time.