Hello Vlad and welcome to the forum.
See the roulette table layout attached.
The red snake roulette bet consists of the following RED numbers that in the roulette table form the shape of a zig-zag or "Snake" :
We bet 12 red numbers. The 6 Red number that we do NOT bet are: 3-7-18-21-25-36
Since the layout of the numbers on the table is the same on American and European roulette, this bet can be applied on both.