As part of the Summit Series, the L1s are engineered for long, multi-pitch routes in shifting alpine environments. And they're all about ensuring you move as freely as possible. They're made from durable nylon, so they brush off close encounters with rock. Add some elastane to that mix along with articulated knees, a gusseted crotch and taped seams and these trousers won't restrict even broad-stance stemming moves. And you can tighten the hems around your ankles or pull them up around your calves using the cinch cord if the temperature starts to climb.