Polartec hopes its new Heat fabric—with electrically heated panels—will lighten your cold-weather load

MARCUS SWANSON

The North Face MET5: the first battery-operated fleece jacket

DUCK HUNTERS and slednecks have for years kept themselves warm with battery-powered socks and plug-in suits—devices long ridiculed by, well, just about everyone else. Fair enough: These getups are typically heavy, impractical, and downright embarrassing to wear. So, you say, how does that explain Polartec's new Heat technology, a system of electrically heated panels that will be sewn into The North Face's new MET5 jacket? Glad you asked. If Polartec is right, Heat could eliminate the need for a heavy down parka. "This is the first time," says David Costello, marketing director at Polartec parent Malden Mills, "that somebody can maintain their core temperature with a press of a button."

Cool. Or rather, hot. A Malden Mills­designed matrix of filaments—each one-fifth the width of a human hair—lies at the heart of the Heat system. The mesh (the company won't say what it's made of) carries current from a small rechargeable battery unit. Turn off the switch when you're exerting yourself; set it for low (105 degrees) or high (114 degrees) when you're sitting on the chairlift. The jacket will stay hot up to five hours; and when it's time for the laundry pile, just unplug the batteries and switch, and toss it in the Maytag.

Malden invested almost four years developing Heat, but it wasn't until a field trial in September that The North Face knew they'd signed on to something novel. A volunteer clad in a MET5 jacket rapped into a crevasse on Mount Rainier—then testers shoveled snow on top of him. "When he was fully buried, he started violently shaking," says Thomas Laasko, a project manager at The North Face. "Then he turned the jacket on and warmed up in four minutes. That was the point at which we said, OK, this thing's not a gadget.'"

The North Face anticipates that outdoor athletes will clamor for the MET5 when it hits the shelves this fall, but it ain't cheap—$499 a pop. Weight is also a concern—the batteries and the controller tip the scales at 11.6 ounces—but both companies believe that's a small price to pay for not having to carry extra insulation. And for not freezing to death —Kevin Fedarko