【Expandable Design】Innovative expandable backpack design increases capacity from 25L to 35L, comparable to a 20-inch suitcase, perfect for both daily commutes and business trips. 【Multi-Compartment Organization】Features multiple pockets and layers for efficient space utilization, including a wet/dry separation compartment for toiletries or damp items. 【17.3-inch Laptop Protection】Dedicated shock-resistant compartment safely accommodates laptops up to 17.3 inches, ensuring your device's security during travel. 【180° Opening】Clamshell-style opening allows the bag to open fully flat for easy access to contents, enhancing user convenience. 【Travel-Friendly Features】Equipped with a luggage strap for easy attachment to rolling suitcases, anti-theft password lock, and external USB and Type-C charging ports for on-the-go power. 【Comfort and Durability】Honeycomb breathable back padding provides comfort and reduces pressure, while water-resistant fabric keeps contents dry in light rain. Specifications: Model: CB-8309 Material: Polyester Weight: 1.35kg Dimensions: 33 x 16 x 47cm (Unexpanded), 33 x 22 x 47cm (Expanded) Capacity: 25L (Unexpanded), 35L (Expanded) Laptop Compartment Size: 32 x 43cm (Fits up to 17.3-inch laptops)