Printing on Demand with digital technology is a way to print items for a fixed cost per copy, regardless of the size of the order. While the unit price of each physical copy is greater than with offset printing, the average cost is lower for very small print jobs, because setup costs are much greater for offset printing.

POD has other business benefits besides lesser costs (for small jobs):

Technical set-up is usually quicker than for offset printing.
Large inventories of a book or print material do not need to be kept in stock, reducing storage, handling costs, and inventory accounting costs.
There is little or no waste from unsold products.

These advantages reduce the risks associated with publishing books and prints and can result in increased choice for consumers. However, the reduced risks for the publisher can also mean that quality control is less rigorous than usual.

Here is the size Printing on Demand,

Size	150 x 150mm
Pages	8 pages
Materials	PVC outside, inside is foam
Packing	polybag with header card
Price	USD 0.5 for the MOQ 3,000 pieces/title