These Walking-Powered Shoe Insoles Don't Need Batteries to Warm or Cool Your Feet
Battery-powered, self-heating insoles can help keep your feet extra toasty during winter activities, but few of us want to charge our shoes. Solecooler's Climfeet insoles promise to not only warm your feet without the use of chemical reactions or batteries, but to also cool them when temperatures soar. Better yet, the...