Three-dimensional shape business bag, high value and more contentErgonomic burden-reducing system - The air deflector back panel design allows air to pass freely, keeping your back dry at any time.Thickened pearl cotton on the back, decompression and impact resistance, travel and trip without burden.Scientific shoulder straps - Thickened and widened ergonomic shoulder straps balance the force, protect the spine and reduce the pressure on both shoulders.How can your mobile phone run out of power when you are out and about - External USB port for charging, convenient and fast!Texture fabric + waterproof, soft and comfortable backpack fabric with delicate texture, waterproof design, moisture and humidity resistant.