This backpack is designed with two sizes, 15.6 inch and 19 inch. The 19 inch backpack not only has its own 19 inch computer compartment, but also has ingenious contraction function, which makes the backpack suddenly grow larger. Its internal capacity can reach 39 liters, which is equivalent to the capacity of a 20 inch trolley box. In addition, the bottom of this backpack is added with rubber foot pads, which can not only protect the backpack from wear, but also clean and sanitary. RFID anti-scan lining with hidden back pocket has become a major feature of tiger nu  backpack.