These 'lunch boxes' are often refered to by the japanese name, 'bento box', and are used to transport your energy bars and gels when riding longer distance. You can fill it with about 5 bars or 10 gels, depending on their size. This convienent pocket is attached to the stem and top tube with 4 velcro straps. The net top can be pulled tightly down or left loose, with the velcro closure. The whole pocket is very light, weighing about 2 oz. There is an additional small pocket inside for holding a chapstick or other such form. Nutrition box, 5.1x1.6x3.1" (13x4x8 cm), 420D nylon material, reinforced with plastic side stiffeners, net material over the top, fastened with velcro, no branding, small pocket in back for chapstick.