This product requires manual compression of the bag to extract air, or you can configure a pump to operate it yourself. Thank you

Product Name: Vacuum Compression Backpack
Material: Waterproof Oxford cloth
Size: 49*32*15CM
After expansion: 49*32*20CM
Capacity: can hold a 17-inch laptop
Separate laptop bag
Using the vacuum compression method:
1. Open the compressed vacuum lined bag
2, put the clothes on the air-tight zipper
3. Open the one-way exhaust valve
4. Press to exhaust the air inside
Function:
Breathable back
Comfortable foam shoulder straps
strap
Anti-theft zipper pocket on the back
Waterproof/wear-resistant/moistureproof
Wet and dry separation area
vacuum compression airtight
password
boarding
Large capacity = 24-inch luggage