What products can be ordered through On-Demand Printing? QuantumPostcards Support September 01, 2017 01:06 Updated Postcards, flyers, booklets, brochures, business cards, door hangers, and more. Related articles Designing & Uploading a Digital Print File Will someone review my order after it has been placed? What file formats are recommended for On-demand Printing services? Where can I find Panoramic Postcards and Mailed Flyer media types to use for my mailings? What paper stock is used for the mailings?