Premium material: The backpack is made of quality TPU and polyester material, wear-resistant and durable to use Large capacity: Designed for storing ropes and other essential equipment used in outdoor activities such as tree climbing gears, rock climbing gear, and caving, hiking equipment Internal sealed bag: The internal waterproof compartment is suitable for storing digital products, such as mobile phones/cameras/electrical appliances, etc., which are water-proof, making your electronic devices safer Elastic band: The outside of the backpack has elastic ban, which are suitable for holding wet clothes, shoes, etc., and are tied and fixed outside to prevent other items in the backpack from getting wet Air nozzle: When you want to go swimming, you can fill the bag with air to increase the buoyancy of the backpack. The backpack can act as a swim buoy; when traveling outdoors and climbing, let out the excess air in the bag to make travel easier Suitable scenes: Perfect for outdoor hiking, camping, rock climbing, cycling, etc Specification: Size: 21*21*45cm Weight: 460g Capacity: 16L Material: TPU+polyester