Okay, so these Brooks Caldera trail runners are basically your ticket to escape those boring city routes. They're designed specifically for hitting the dusty trails with responsive, energizing runs. First off - they're part of the Sustainable Apparel Coalition, which is pretty cool. They've got neutral support type with lightweight, flexible cushioning that's perfect for trail surfaces. The 4mm differential gives you that natural feel. The upper is this protective double-layered mesh and synthetic material with strategic stretch - fits like a dream and feels nearly seamless. There's a lace-up closure with this lace-garage feature for added security, plus an integrated Gaiter Tab at the heel if you use hook-and-loop gaiter systems. The tongue and collar are nicely padded, and the smooth fabric lining feels great inside. The removable foam insole is handy, and the midsole geometry gives you inherent protection and stable ride even when you're getting tired. The BioMogo DNA midsole adapts to your every stride with dynamic cushioning. Bottom line - the sticky rubber and HPR Green outsole has these lugs with high surface area that give you killer traction both uphill and downhill. Weighing in at just 9 oz for size 9 medium width, these are legit trail shoes that won't weigh you down. Perfect for when you want to ditch the pavement and hit some real terrain!