1. Expandable up to 39L: Expandable width by 6cm with inverted V-shaped zipper design, achieving 30% capacity increase. (Standard 15.6-inch version cannot be expanded.) 2. Multi-compartment design: Dedicated laptop compartment + main compartment + front combination pocket + front zippered pocket for organized storage. 3. Headphone port & USB charging port: Enhanced convenience for on-the-go use (Requires self-provided power bank to utilize charging function via internal port). 4. Double-layer quadruple-tooth anti-theft zipper: Puncture-resistant and tear-resistant construction with lockable zipper pulls for dual-layer security against theft. 5. Backside features: RFID-blocking pouch + honeycomb-patterned breathable back padding for comfort and anti-scanning protection. 6. Water-resistant fabric: Weather-resistant protection keeps contents safe in rainy conditions. 7. Material: 1011 foam material 8. Dimensions: 25 x 18 x 42cm (15.6-inch) | 30 x 22 x 46cm (19-inch)
