A two-piece fastening material that features hooks on one side and a swath of loops on the other. When pressed together, the sides entwine like a weed’s spiked seedpod clutching your wool sweater. Indeed, Swiss George de Mestral got the idea from burrs sticking to his pant legs in 1941, making it an early example of biomimicry in industrial design. Velcro’s outdoor applications include hard-shell cuffs, ski-boot power straps, and messenger-bag closures. One drawback: the stuff is loud.