Many of us know The Sharper Image best as a purveyor of massaging lounge chairs (which makes their stores a must-stop location in the mall), a chronic pusher of ozone generators, and as a perennial favorite in SkyMall catalogs as we bide our time on the redeye.

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Hough is placing an order with Purfresh, which recently switched to a rental system for the generators, for 27 more ozone cabinets.

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They take you inside through a tunnel that smells of ozone and let you look through glass windows at giant, whirring generators while the guide unfurls the mysteries of turbines and transformers for the rapt crowd.

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