Fire Up the Choir $20.00 Inside Message Blank Inside Packages of Heartstrings® cards are shrink-wrapped and sold in sets of 10 cards with envelopes. The actual card size is 4 1/4" x 5 1/2". Fire Up the Choir quantity Add to cart SKU: 308. Categories: Birthday, Humor. Tags: art cards, art greeting cards, birthday cards, unique birthday cards, unique cards, unique greeting cards. Related Products You are the Rock in My River $20.00 When You’re Over the Hill $20.00 Starve a Cold, Feed a Retreiver $20.00 Life is Sweet $20.00