Lee Bagby always knew he wanted to invent something. Then, one day, it hit him.

The heating, ventilating and air-conditioning salesman from Arvada had a brainstorm as he stared at a device he'd tried to sell every day for years.

Bagby sold wheel heat exchangers, which absorb the heat from air being purged from buildings and use it to heat up the air being pumped in.

He realized that he could make miniature wheel heat exchangers, insert them in a neck gaiter, and sell the masks to people looking to stay warm outside in the winter.

Introducing the Psolar.EX mask, on sale as of today at McGuckin Hardware for $30.

The mask works by trapping the warmth from the breath you exhale and using it to warm the cold air you inhale. Bagby makes the "lightweight thermal conversion module" in his basement.

He says the mask is the perfect outdoor accessory for climbing, hunting, fishing, running, skiing, snowmobiling, snowshoeing and walking. Maybe not a bad idea for the chairlift and that zero-degree Broncos game, either.

The mask, which Bagby first introduced at the Outdoor Retailer show in August, is about to face its first winter. It will hit the shelves today alongside a competing product that has existed for four years.

"I'm not the first one to do it, I'll admit that, but I think it's the most practical way to do it, using the latest technology," Bagby said.

In 1998, Memphis-based PolarWrap introduced its "Exchanger." That model sells for $60 and features a sewn-in copper mesh fabric that the company says does the job better than the new Psolar.EX.

Bill Motley, executive vice president at PolarWrap, said he's tried Bagby's version in his zero-degree walk-in freezer. He said he got cold.

But Bagby insists that's just a lot of hot air.

"Mine works just as well, and it's a lot more simple," Bagby said.

Only time will tell how the two products stack up.

This winter, world-class mountain climber Ed Viesturs plans on trying out the

Psolar.EX. So does Iditarod champion Martin Buser.

John Rhoades, assistant curator at the national Ice Core Laboratories in Denver, recently stuffed two Psolar.EX masks in his duffel bag on his way to Antarctica. His boss, curator Geoffrey Hargreaves, said Rhoades has used the mask while working in the deep storage labs with ice cores from Antarctica and Greenland.

"He seems to think they work pretty well," Hargreaves said.

Bagby said he's working on a lighter model for joggers and another one for medical applications.

For more information, go to www.psolar.com [ www.NeboGear.com ].