Made of high-quality Polyester waterproof fabric and 210D Lithium Cloth lining material, ensuring the backpack is lightweight, comfortable, and durable for kids to carry. Water resistant, wear-resistant, and easy to clean, providing better protection for the items in the backpack from getting wet and easy to wipe down. Trolley bar designed to carry enough weight and easy to pull, making it convenient for kids to transport their belongings. Backpack size of 16" H x 11" W x 7" D, with a backpack weight of 1.60 lbs. and wheels weight of 2.90 lbs., suitable for a variety of items such as books, computers, clothes, and other small items. Adjustable padded shoulder straps and handles that can be used as a shoulder backpack without the trolley, providing comfort and convenience. Stable trolley design that prevents rollover, ensuring the backpack stays on the trolley securely. Multiple pockets and compartments, including a large capacity main pocket with compartment, 3 front zip pockets, and 2 side pockets, allowing for easy storage of school supplies, tablets, books, folders, umbrellas, water bottles, and more. Suitable for primary, middle, and high school kids, as well as adults, making it a versatile choice for various age groups.