PolyesterSUPERIOR QUALITY: Made with durable, weather-resistant 1200D ballistic polyester to withstand heavy use and harsh conditionsTRAVEL WITH EASE: ScanSmart lay-flat technology protects up to a 17 laptop, opens quickly at airport security, and ensures a hassle-free laptop-in-bag TSA scanORGANIZED & SPACIOUS: Easy access laptop and iPad compartment separate from roomy main compartment. Front organizational pocket for all of your writing utensils, pocket notebooks, and keys. Front, large, U-zip pocket for quick access essentials. Two, breathable, side compartments for an umbrella, oversize water bottle, or a change of clothes.COMFORTABLE: Contoured shoulder straps with mesh fabric and adjustable side compression straps. Padded back panel with Airflow ventilation technology for added support and comfort.DIMENSIONS: Exterior Dimensions 18.5 X 13.5 X 9, Laptop Compartment Dimensions 17 X 12.5 X 2.5