External dimensions: 36 x 41cm (L x H). The large-capacity design is waterproof and can accommodate a laptop. Made from high-quality polyester fiber, soft zippers and a breathable mesh back, it is lightweight, comfortable and durable. Adjustable ring type adjustable opening and closing, freely adjust the length of the strap, reduce weight load, effectively protect the back and shoulders, and make your life more comfortable. Perfect for everyday use, excursions, etc. A great backpack for sports, travel, hiking, shopping, camping, or other outdoor activities.