The innovative, ventilated Aeroflex Control suspension system is uniquely comfortable: Apply tension to the suspension system for sweat-inducing rides up the mountain. For the ride downhill, the system can be converted into a body-contact back. This brings your load's center of gravity closer to your body to improve bike handling on uneven, winding trails. The backpack is large enough to hold a change of clothes and items for multi-day tours including a stay in a mountain chalet. The main compartment can be divided into two sections. There is a bottom access compartment at the bottom. Hydration bladders up to 3 l volume can be stored in a separate compartment. A split tool compartment with mesh inserts at the front offers good organization options for tools and maps. You can still access the phone compartment that's well protected from the weather, even when the rain cover is on. Small items can be stored in the mesh side pockets. An adjustable sternum strap, removable helmet holder, side compression straps, hydration system port, key and safety light holders are all included as is a rain cover with reflective print. The plus in the name stands for the adjustable compartment that opens at the top and is perfect for your rain jacket or a wind jacket on longer journeys. The indestructible material has been made permanently water-repellent with PFC-free Eco Finish.