No matter the type of lottery draw game you're playing, winning numbers are always randomly selected and visible to the viewer-both during the "mixing" process and the numbers selection process. There are two main types of lottery draw machines: gravity pick and air mix. No matter what kind of machine is used, viewers can see the rubber balls at all times as they travel through a transparent tube, which gives viewers confidence that the drawing is not being tampered with or fixed.
Gravity pick lottery machines are the most commonly used machine-for major drawings like Mega Millions and Powerball, you can usually count on seeing one. This machine, complete with spinning paddles that rotate in opposite directions, mixes the balls until they drop out of the bottom of the chamber one by one.
Air mix lottery machines are usually used in games like Pick 3 or Pick 4. The machines have a chamber filled with numbered ping-pong balls that are moved by jets of air from a fan located at the bottom of the drum. The balls move up and out of the chamber through a tube and are pushed out onto a tray.