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This hat will cool you down faster than A/C

Cool Smile cooling hat

While it won't help battle the flop sweat you'll suffer once it's clear everyone's staring at your shirtless paunch at the beach, this black ballcap will keep you comfortably chilled out in the sweltering heat, thanks to its unique built-in cooling system.

Peltier device diagram

The (fairly) normal-looking headgear employs something called a "Peltier device" above the brim, which harnesses the power of thermoelectricity to suck heat from your forehead via voltage from a AA battery. And in under five minutes, it can bring its temp down to 60 degrees, then stay that cold for almost two hours.