He still uses the same pack, but now divides the gear between the pack and a sled. “I keep telling myself it has got to last me one more year,” he said. “Some of the rivets have popped out because I carry too much weight in it.”

Some of the gear is handmade. Helen and Chris Scotch, both 38, of Bend, Ore., pull their sleds with bungee cords. The forgiving stretch of the cords makes the movement of the sled less jarring. They also have lightweight handmade ponchos, and to keep their water warm Chris Scotch used insulated foil Bubble Wrap to make covers for their water bottles. He found it so handy he ordered an entire roll from an industrial distributor. “I think it works better than neoprene because there is more air to insulate it,” he said.

Chuck Lindner, 44, of Warroad, Minn., wears an anorak made by Lure of the North, a company based in Ontario. The jacket’s material is of Egyptian sailcloth that is breathable and windproof. The hood is trimmed with coyote fur. “When it’s windy, the advantage of a fur ruff is it creates its own microclimate, so at 30 below you won’t need a face mask,” Lindner said.

Jared VanderHook, 32, of Minneapolis, had a gear bag made out of Cuben Fiber, a material used for yacht sails. The friend who built the bag also created a website called Fastertracks, which processes the GPS signal from his SPOT tracker, which uses satellite technology and is mounted on his sled. His girlfriend follows him on her computer; other racers and their support teams were also using the software this year.

Cellphones are allowed, but taking one might not be worth it because coverage is spotty. Tracking devices are permitted, but as Krueger, the race director, pointed out, it doesn’t take away from the rugged independence of the race.

“We discourage snowmobile rescues,” Krueger said. “We encourage self-rescue. If you’re tired or cold or sore, we want people to get to a checkpoint. We don’t want them dependent on snowmobiles to get out. This is not a babysitting race. This is one of the hardest races in the world, and you’re supposed to be self-sufficient.”