Rainbow — Schematics

Rainbow is the water-filtration vacuum cleaner system built by Rexair LLC of Troy, Michigan. Rexair was founded in 1929, and in 1936 engineer Russ Hill — inspired by watching street cleaners use water to suppress dust — pioneered the use of water as a vacuum's primary filtration medium under the slogan "Wet Dust Can't Fly." The system was rebranded "Rainbow" in 1955 and the brand has been refined through eight generations of models.

Rainbows have always been sold direct, through independent distributors, never in retail stores. The current Rainbow SRX and the long-running e-Series and SE machines all use the same water-basin filtration concept, and Rainbow ownership tends to span decades — keeping parts demand steady for HEPA Neutralizer filters, hoses, power nozzles, brush rolls, motors, and the family of attachments that have remained largely compatible since the e-Series era.