Made of Water Resistant and Sturdy Polyester Fabric with metal zippers.Comfortable soft padded back design with thick but soft multi-panel ventilated padding, gives you maximum back support. Breathable and adjustable shoulder straps relieve the stress of shoulder. Foam padded top handle for the long time carry on using.External USB charger (with waterproof cover) and built in charging cable inside,this usb backpack offers you a more convenient way to charge your phone while walking.Please noted that this backpack doesn't power itself, usb charging port only offers an easy access to charge.Not include the bank.

Quantity	100	500	1000	5000	10000	50000
Price	$73.69	$69.52	$61.99	$49.69	$37.28	$25.99