Card is printed on heavy white cover stock. Outside: Happy Birthday to YouThe inside is left blank for your personal message. Dimensions: Each card has a single fold and measures 5 1/4" x 5 1/4" and comes with an envelope. Please note that square envelopes require extra postage. Buy six cards, get one free! (Free card must be of equal or lesser value.) Add seven cards to your cart and the amount for the seventh card will be subtracted from your total. Tip: If you would like to order more than three cards, get the best deal on shipping by combining your card order with a larger item, or a box of up to 20 cards.