About thrml.

AirCap Technologies Inc. makes the AIRCAP 1™, sold under the thrml. brand. One company, one brand, one product — built in and shipped from the United States.

Who we are

thrml. is the consumer brand of AirCap Technologies Inc., based in Liberty Lake, Washington. The AIRCAP 1™ was conceptualized and designed by a spa-industry veteran with more than 25 years in the hot tub business — and one recurring conversation: customers asking whether there was anything better than the 40-year-old foam-wrapped-in-vinyl cover that gets heavier every season.

What we make

The AIRCAP 1™ is a patent-pending replacement hot tub cover with a welded drop-stitch air-cell core instead of foam. Because there is no foam, there is nothing to absorb water: it weighs 40–45 lbs on day one and 40–45 lbs in year five. It comes in six sizes covering square spas from 77" to 94", fits roughly 90% of hot tubs on the market, is engineered to comply with ASTM F1346-23 safety-cover requirements, and is backed by a 3-year warranty. Every cover ships free within the continental United States.

Where to find us

We sell direct through this store and through a growing network of hot tub retailers — find one near you with the store locator. Retailers can learn more at retailers.thrmltech.com. Not sure which size fits your spa? The Spa Fitter lists 262 models across 20 brands, and the SureFit™ guide covers everything else in two measurements.

Contact

AirCap Technologies Inc., doing business as thrml.
1324 N Liberty Lake Rd Ste 2161, Liberty Lake, WA 99019
feedback@thrmltech.com · (425) 931-8496
Or use the contact form — we answer within one business day.