Sturdy cardboard - delivers what it promises

The pro-boxes are very stable and can withstand when you loads of books to the brim (with tow which is then another matter). From my 50 boxes of books no one has broken down, and all can be reused.

The box also has a good size, and so I finally half my household is packed (on Amazon, I could always afloat reorder when I ran out of stock :-))

I had at first a few cartons of hardware store, which each were even more expensive with 2.39, but not qualitatively heramkamen to the professional board.

Delivery within 2-3 days was also without problems.

Conclusion: can 100% are recommended.