15.6 inch External USB Interface Laptop Backpack Waterproof Computer Bag(Black)

1. Selected materials, waterproof and dirt-resistant2. Computer anti-shock isolation layer, effective anti-shock and anti-pressure, protect the computer3. External USB conversion interface, comfortable decompression shockproof back cushion4. Back lever insertion design5. Capacity: 20-35L (accommodating 14-inch computers, umbrellas, books, glasses, wallets, etc.)6. The internal structure of the bag: zipper pocket, mobile phone bag, credential bag, sandwich zipper bag, computer pocket7. Opening method: cover type8. Material: Oxford cloth9. Function: breathable, waterproof, wear-resistant, anti-theft, anti-vibration, lightening10. Size: 44x32x13cm