Knack Series 1 Medium Expandable Backpack - BLACK NWOT (in original box)

The Series 1 Medium Knack Pack is a popular, versatile, and professional expandable backpack designed to seamlessly transition from an everyday slim commuter bag into a 2-to-3-day travel luggage piece. Retailing around $235, it combines hidden compartments and specialized pockets, fitting under most airline seats as a personal item.  Key Specifications & MaterialsDimensions (Unexpanded): 19 high x 12 wide x 4.5 deep  Capacity: 27 liters (main compartment) unexpanded, expanding up to 39 liters total with the packing compartment zipped open  Weight: Approximately 2.11 lbs  Materials: Custom water-resistant 1200-denier two-tone polyester exterior with a stain-resistant, antimicrobial 150D nylon interior lining, paired with YKK water-resistant zippers.  Core Features & Organization  Expandable Packing Compartment: Features a patent-pending hidden zipper compartment that unzips suitcase-style to reveal a large area fitting 2 to 3 changes of clothes.  Dedicated Laptop Pocket: A padded, easy-access side-zip pocket on the back panel accommodates laptops up to 15.6 or 16.  Smart Exterior Pockets: Includes a fleece-lined top pocket for sunglasses or phones and a distinct V-shaped/triangular front organizational compartment with RFID-blocking card slots.  Hidden Water Bottle Pocket & Trolley Sleeve: A side water bottle pocket zips away cleanly when not in use, and a luggage trolley sleeve allows the bag to slide over rolling suitcase handles.  Stowable Straps