From what Ive heard, Aerus originated the OBT upright design with the Lux 4000 (followed by the Lux 6000). Customer reception was luke warm overall due to weight and balance issues, so Aerus sold the manufacturing rights to ProTeam-Emerson, which manufactured its own lines:
Cascade
ProCare
ProForce
In addition it private-labeled several renditions:
Aerus's Xtreme Plus
Sanitaire's SC6600 & SC6600A; "System Pro" SP6610 & SP6610A
Pullman-Holt's "Rug Boss" UV3, UV5 & UV10
Clean Obsessed's CO101
Dust Care's HD-2 & DCC-2HD
Bissell's BGU1000 ("Big Green Upright")
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Most of Aerus's vacuum cleaner motors have been manufactured by JEI of Hong Kong since circa 2002.
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