Airlines count bags, not how much is in them, which is the whole argument for compression. This pack ships with a rechargeable mini vacuum pump that draws the air out of bulky clothing so a longer trip fits inside a single carry on, and a 1.77 in. expansion layer opens it to 65 L when the outbound load simply will not compress further. The pump is not single purpose either, switching to a camping light with three modes once the packing is done. A TSA approved lock secures the zippers so an inspection ends with the lock reclosed instead of a forced zip. Inside, a wet and dry separation keeps damp kit off clean clothes, with a card pocket and an anti theft pocket for documents and valuables. The shell is PVC leather, water resistant and resistant to scratching and abrasion, with reflective strips for visibility after dark, padded shoulder straps, a breathable back cushion, a USB charging port, a luggage strap, a mini compass and a whistle buckle. Finished in black. Color: Black Water-Resistant PVC Leather with 900D Coated Fabric.