>> Glove-friendly zippers
Snip off the dinky, hard-to-grasp fabric tabs that come standard and buy a healthy length of 3mm parachute cord. Cut it into six-inch lengths (to form three-inch-long loops). Attach one to every zipper slider—on tent doors, vestibules, jackets, pants, and packs.
>> A survival bracelet
"You always need extra P-cord for rigging tents, making clotheslines, and fixing straps," says Mt. Washington meteorologist Ryan Knapp, who wears a bracelet or belt made from woven parachute cord (starting at $19, survivalstraps.com). Or make your own; see how at backpacker.com/survivalbracelet.
Pens freeze up, but, says Clark, "You can always sharpen a pencil with a knife."
>> A tent brush
"You can use any small kitchen brush or even a cheap paint brush," Larsen says. "They’re light (a couple of ounces). Use one to brush off the frost from your clothes, boots, and pack before entering the tent." Also: Sweep snow out from inside your shelter.