Product Dimensions: Large:30*14*45 cm/11.8*5.5*17.7".  The Logo s color is white during the day. In the natural light or light irradiates about 10-20 minutes can produce a good luminous effect it could be maintained about 4-6 hours. If the light is strong and lasts for a long time the luminous effect and duration will be enhanced. After absorbing light the color of the logo will glow in the dark as the picture shown. Breathable canvas material. Cotton handle cotton strap Metal zipper. Smooth nylon fabric lining.  Ample roomy Shoulder strap can freely adjust the length.  It is a great gift for anime fans.  Let s crazy for it Whether you are traveling outdoor sport going to school.  Multi function Super space this bag is your best choice.  Too many choices to choose just follow your heart. Young people s favorite Fashion anime music pattern Casual style. Male and female generic luminous backpack make you or your kids more attractive and safe at night. Inside includes laptop compartment applicable to 14-inch notebook computers. Material:Oxford fabric Canvas. Size: L:30*14*45 cm/11.8*5.5*17.7"