Total of four compartments:
Main compartment 18" x 10" x 5" with one zipper and one mesh pocket
Second compartment 15" x 8" x 2"
Front top compartment 4" x 7" x 2.5"
Front bottom compartment 10" x 8" x 2.5"
Hydration compatible
Size : 18" x 10" x 10"
