get a 50' ball of cheap twine at dollar general and make
a simple mesh net around your box. that will hold almost
any box together, and will prevent stuff from falling out in
case of tears.

if you cut a couple pieces of 6" pvc and tie to each
end, the luggage handlers will have something to
grab aholdst of instead of the handholes in the
carton, which often just tear open.

the box in the photo is cobbled together from old
post office shipping boxes. returning from burma,
had already been through three flights and a
month of storage in a mildewy guesthouse attic.