This hi-tech backpack has an ingenious harness system that’s quick and easy via one push-button buckle with no need to re-adjust the harness straps every time you put it on or take it off. Once it’s set, just click. It’s also angled out from the underarm area for total freedom of movement. Combined with a removable waist strap, what you’ve got is an unequaled level of high speed stability. 3M reflective areas along front and back. Main compartment with YKK water-resistant zipper has 1220 cubic inches of space. Side access pocket also has a YKK water-resistant zip and there’s an internal zippered mesh pocket, too. An internal reservoir pocket with compression straps fits a 3 liter hydration insert (not included). Add over 300 cubic inches of space by attaching a US-5, or over 600 cubic inches with a US-10. The overall length of the pack has a shorter back to allow it to be worn above waistpacks. 18"×11"×6".