Nathan's Firestorm Hydration Race Vest readies you for marathons whether you're running or cycling. Waist and sternum straps secure the breathable mesh over your shoulders and on your back for a bounce free ride. Nathan included a 2L bladder with a quick release valve for all the water you need. Apart from the main compartment, there are also loops for your helmet, side stretch pockets for water bottles, front stash pockets for energy gels, and an organizer pocket for your wallet and keys. Reflective trim keeps you visible in low light.