• This expandable backpack can meet your needs, which can be expanded from a 23L commuting backpack to a 39L large backpack
• Large capacity, it can organize your clothes, laptop, tablet, cell phone, headphone, etc
• Made of quality nylon surface+polyester lining, it is wear-resistant and scratch-resistant
• With a fixing luggage strap, convenient to keep it stable on your luggage case, easy to carry to travel
• With a USB port to charge your phone conveniently via connecting your own power bank 
• It's perfect for travel, business, camping, or cruises

Specification:

• Size: 46*30*20~28cm
• Material: nylon surface+polyester lining