Rainbo

Rainbo, manufactured by Keeney and Sons of Chicago in 1932, is one of the earliest known pinball machines. As such, it holds a significant place in the history of the game, predating the introduction of flippers by roughly fifteen years.

Rainbo is notable for its pure mechanical (PM) design, meaning gameplay relies solely on physical mechanisms with no electricity or electronics involved. It was offered for 1 cent or 5 cent play, letting players choose the denomination of their game. The playfield included ten trap holes and, per most known photographs, four free-play holes (though a manufacturer's ad references only two). Balls were made of china, an unusual material choice even for the period.

The design and art on Rainbo are relatively generic for a machine of this period, with no discernible theme or distinct visual elements. The availability of steel and wood stands as optional purchases highlights an early example of pinball manufacturers offering customization options. Little else is known about this machine beyond its specifications, making it an intriguing artifact for enthusiasts of vintage tabletop/counter games.