Either ball must be successful for 'inside' bets to win.

For example, for a bet on Red win, both balls must land in a red number.

Both balls must be successful for 'outside' bets to win.

Most of the layout is the same as conventional roulette.

An ordinary single- or double-zero wheel is used.

In addition the player may bet that both balls will land in any one number. On the outside bets, both balls must win, but the pays are more. With the inside bets, the player has two chances to win, but the pays are less.

The betting layout is mostly the same as standard roulette. He assured me that an independent lab did tens of thousands of spins and the probability of the two balls landing the same number is about the expected 1/38, assuming they two outcomes were completely independent. At least I wondered this and annoyed the game maker with physics questions at the gaming show for much too long about it. You might also wonder if the probability of the two balls landing in the same number is about the expected 1/38, assuming they the two outcomes were completely independent. They travel at the same speed so the second ball always trails the first one.

The game uses compressed air to shoot the two balls out of a tube almost simultaneously. You might wonder about how they keep the balls from hitting each other in a physical game.

Later, in November, 2016, I noticed it at an Internet casino using Felt software. I first saw the game at the 2013 Global Gaming Expo and later at the Tropicana in Las Vegas on February 18, 2014. Double Ball Roulette plays like regular roulette, except with two balls.

Is double zero rare in roulette