ISF1007 Features: * Air flow back provides extra comfort for maximum back support * Padded laptop sleeve with elasticized compression strap secures laptops up to 15.4 screen * Audio headphone portal for convenient music playback * Large organizer front zippered pocket for compartmentalizing items * Contoured shoulder straps are ergonomically designed with added padding for comfort * 840 Ripstop nylon * 3.1 lbs (with batteries) * Designed for ages 14 and up * Fits laptops upto 15"" * The alarm system can run continuously for up to two hours before the batteries must be replaced * When the batteries are too low to effectively operate the alarm system, a red LED light will flash for 72 hours to indicated replacement of batteries * The strobe light can be seen up to 400 yards away * The siren signal can be heard for over a 1000 yard radius on both sides of the user Specifications: * iSafe Backpacks & Bags operate with two 9 volt alkaline batteries Dimensions: * Overall dimensions: 18"" H x 15"" W x 11"" D