One Size At home hiking, biking and more, the Tempest Jr. is designed for girls aged 4-12 years old. Featuring comfortable and breathable AirScape® suspension and a seamless harness-to-hipbelt wrap that flexes with the child's body during the sport of their choice. Constructed with durable, lightweight fabric; easy-to-reach hipbelt pockets; an external reservoir sleeve; and loop for a blinky light. FEATURES Dual-zippered panel access to main compartment Internal zippered mesh pocket with key clip Stretch mesh front panel pocket Side stretch mesh pockets Top panel zippered slash pocket LidLock bike helmet attachment External hydration reservoir sleeve Easy-access, expandable stretch mesh harness pocket Dual mesh hipbelt pockets Blinker light attachment(light not included) AIRSCAPE BACKPANEL Injection-molded AirScape framesheet with die-cut foam provides a close-to-body stable fit while offering flexibility and ventilated airflow channels for active use Mesh-covered foam lumbar for lightweight and comfortable contact surfaces BIOSTRETCH HARNESS Integrated BioStretch seams offer maximum flexibility without sacrificing stability for dynamic body movement Spacermesh over die-cut foam provides breathable, comfortable contact surface Harness system easily adjusts to fit various torso lengths Adjustable sternum strap with safety whistle buckle BIOSTRETCH HIPBELT Seamless lumbar-to-hipbelt body wrap and BioStretch seams offer maximum flexibility without sacrificing stability for dynamic body movement Spacermesh over die-cut foam provides breathable, comfortable contact surface Crossbody ErgoPull hipbelt system to pull lumbar into body O/S VOLUME 671 IN 3 / 11 L DIMENSIONS 6.69H X 9.84W X 15.35D IN. WEIGHT 1.2 LBS. FABRIC MAIN bluesign®-approved recycled 100D x 210D wave check high-tenacity nylon, PFC-free DWR ACCENT bluesign®-approved recycled 420HD nylon packcloth, PFC-free DWR BOTTOM bluesign®-approved recycled 420HD nylon packcloth, PFC-free DWR WARNING: This product can expose you to chemicals including dimethylformamide, which is known to the State of California to cause cancer. For more information, go to oehha.ca.gov/proposition-65/about-proposition-65