It's works great! You can use them in parties. Or they work great with just water, but with alcohol you need to drink it till the last drop to make it stop flicking. You can always wash them with water after the party ends and they will stop flicking when they dry.
and the light is strong.

Great gift!! When you put it on the table to a person and fill in his/her cup before the tost, it's a big surprise to see blinking cup.

It's cheap.
It's perfect!
It will come very fast.
It's perfect for a party

Looks as made of glass

It is large enough for strong alcohol!

Alcohol forces blink even after drinked

When you are to put blinking out - lay the cup down to it's side. After some seconds small drop of liquid will release contacts. Do not turn cup