Electrolux Corporation introduced the 'Ultralux' model name in 1990 with the revised model number 1521 tank cleaner. Continuing revisions and cosmetic changes were reflected with model name additions:
• Ultralux, factory paired with unlighted power nozzle 1622, 1990-91, light sand gray trimmed in navy
• Ultralux LX, factory paired with lighted power nozzle 1692, 1991-92, light sand gray trimmed in navy
• Ultralux Classic, factory paired with lighted power nozzle 1693, 1992-94, navy trimmed in light sand gray
The Sidekick which sold during this time was the model 1562 (earlier ones had a black reset button instead of a switch and were not identified with a model number.
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In the early 2000s, the model name was reused for an indirect sales tank cleaner called 'Ultralux 2000', model number C151C, factory paired with unlighted power nozzle N115U. Its main color was light sand gray (or something similar), and it was trimmed in black.
The 'Ultralux' moniker was also put to use for the 80th anniversary model number C152E tank cleaner in 2004. When the 'Aerus' logo was added the model number was changed to C152F. The factory-paired power nozzle for both was model number N115S. Colors were light sand gray (or something similar) and regatta blue.
Sidekick model number K119M in light sand gray was likely sold as the customer option for the 21st Century Ultralux's, due to its matching main color.
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Incidentally, there was also a rebadged upright cleaner sold in the early 2000s as 'Ultralux by Electrolux', model number U160A.