Bundling up has never been sleeker, thanks to Chicago-based denim company Mugsy Jeans. With its new ThermoStretch line, there’s no need to choose between form and function once the weather outside turns frightful. Even better: The jeans are specifically designed to offer comfort both while commuting and in cozier indoor climates. “I remember one buddy was complaining about standing on the L platform, absolutely freezing, and he’d have to wear long underwear to prevent getting frostbite,” says founder Leo Tropeano. “But then he’d get to the office, where the heat was blasting, and he was sweating.” The ThermoStretch line maintains the brand’s soft-as-sweatpants feel but kicks it up a notch with yarn-infused denim for further insulating. Best of all, since even the trained eye can’t spot the difference between Mugsy’s special blend of fabric and your typical pair of jeans, ThermoStretch can be your toasty secret. mugsyjeans.com