This product is called a card slider. You will notice that after opening the 4-page piece, that you can easily pull out a card. The card has a debossed portion that fits a gift card or anything similar. We are able to die cut, fold and glue this product automatically! Yes, sizes can vary. There can be more panels. We can inline “clip seal” the piece, on one or two or three sides! Please email for samples. We have got lots.