Paladineer Outdoor Hiking Backpack Lightweight Cycling Backpack 18-liters polyester MATERIAL&DESIGN - Made of abrasion-resistant polyester fabric,duarable.Versatile enough for the everyday and heavy-duty enough for the outdoors COMPARTMENT&ORGANIZED - Main compartment,6 zippered pockets,hydration reservoir sleeve,mesh side pockets.Multiple pockets with hydration sleeve allow easy gear organization ERGONIMIC&COMFORT - Cushioned back support with breathable mesh and air-flow channels to provide maximum comfort;ergonomically designed shoulder harness for comfort ZIPPERS&STRAPS - Zippers made of highest quality to ensure no sticking after a lot of use;fully adjustable shoulder straps to fit a wide variety of people ACCESSORY&CONVENINENT - Helmet mesh cover included to storage your helmet