●The water bottle compartment on the shoulder strap holds two 450ml soft water bottles ●The energy compartment on the shoulder strap can store salt tablets, energy gels, and other items ●Zippered cell phone compartment holds 7.0 inch phone ●Hydration bladder compartment holds 1L hydration bladder, lightweight clothing and other items ●Reflective design on the front and back of the backpack to reflect strong light in the dark environment, increase safety for running and cycling activities at night