Ravensburger, what can I say. I am so glad I found these puzzles through your Mighty Ape website. This firm uses superior heavier cardboard for the backing of these puzzles and each piece is slightly different to another so fit together snugly. If piecing together small groups of puzzle before placing onto main area they do not fall apart like all other puzzles do causing much frustration. Both my husband and I have thoroughly enjoyed completing our Ravensburger puzzles and have passed them onto friends. Thank you Mighty Ape – from a very satisfied customer. Regards to all the apes, Jan