Whether we're hitting the trail for an overnighter or attempting to set a new speed record on the Pacific Crest Trail, the Osprey Exos 48 Backpack is with us every step of the way. With a balanced volume, it keeps our packing habits under control, and it doesn't laugh at the strange things we say to ourselves as we hike. Meanwhile, the AirSpeed back panel and light-yet-durable alloy frame bestows us with breathability by dumping excess heat out of the sides, and cushioned, ventilated ExoForm covers the shoulder pads and waist-belt for extended comfort mile after fast-paced mile.