Re-using waste materials and getting rid of environmentally harmful PFCs is laudable for any product, but these pants also offer a combination of stretch and strength in all the right places. The seat, thighs, and shins are made of G-1000 Eco, a blend of 100 percent recycled polyester and organic cotton that shrugged off grabby bushes on Rocky Peak Ridge in the Adirondacks. But the Keb is surprisingly comfortable, thanks to stretchy panels at the waist and back of legs. They helped us high-step with ease on summit scrambles. The Keb also comes with a PFC-free wax treatment that makes them water-resistant (reapply wax after a few months of hard use).