Product Review

About TIBAG backpack
With a stylish look, this packable go-anywhere pack is for super-minimalists who make every gram count. Ultra-light,durable. The backpack is perfect for day-to-day use or occasional travel. Adjustable breathable straps make it easy and comfortable to carry for all day use.
COMPACT.Folds into zippered inner pocket to fit anywhere. Unfolds from pocket to backpack. Must have on every trip.
MULTI COMPARTMENTS. Features a classic shape with several pockets for storage and organization. This backpack has a roomy main compartment, the 25/30/35L have one front zipper pockets to hold small accessories (the 15L with no front pocket ,it is for kid), one internal security zippered pocket for valuable items and two side pockets for water bottle or umbrella.The outer rubber net can put some accessories.
LIGHTWEIGHT(0.35 Pounds/1 Pounds) and ROOMY(15L/25L/30L/35Liters).A true space saver. Stuff the bag into its own pocket for storage--no extra fees, and unzip it when you reach your destination. Avoid overweight charges, simply unfold from your luggage and use it as a carry on for your excess baggage. 
WATER RESISTANT AND DURABLE.The backpack is made from highly rip and water resistant nylon fabric, provide strengthen and long-lasting performance with minimal weight. Durable 2-way Abrasion Resistant TIBAG Metal Zipper puller with SBS zipper across the backpack.Padded straps reinforce stitching with back panel. Warranty: Our Promise-Lifetime Warranty-Exchange, return, whatever it takes
Dimensions:
15L:Unfold 12.5*9.5*5.25inches, Fold: 7*5.5*2 inches
25L: Unfold: 18*12.5*5.5inches, Fold: 6.75*7.75*1.5inches
30L: Unfold: 19*13.5*7.2 inches, Fold: 9.25*9*2 inches 
35L: Unfold: 19*13.5*8.5 inches, Fold: 9.25*9*2 inches
Warranty: Our Promise-Lifetime Warranty- , return, whatever it takes.
The backpack is perfect and great gift for everyone.