How much does the large size hold?

The large size is rated at about 95 liters, enough for a week of clothes or a full gym and camp load. The extra-large is wider still, while the small and medium suit overnight trips and the gym.

No. The nylon shell is water resistant and handles light rain and spills, but it is not sealed for heavy rain or water sports.

Does it have wheels or backpack straps?

No. It carries by webbed handles or the shoulder strap only, so a fully packed large bag is heavy to move on foot.

Is there a laptop compartment?

No. There is one main compartment plus zip pockets inside and out, with no padded sleeve, so a laptop needs its own case.

What sizes are available?

It comes in small, medium, large and extra-large. Check the listed dimensions for each size, since width and depth change noticeably between them.

Can it be used as a carry-on?

The small and medium sizes can work as carry-ons on most airlines. The large and extra-large are too big for overhead bins and are better checked or used for road trips.