The product is a 2007 SP Authentic #BL-18 Chris Duffy By the Letter Signatures trading card, autographed by Chris Duffy. This card is part of the By the Letter Signatures insert set and features a short print parallel/variety. It is a baseball card from the MLB season of 2007, showcasing the Pittsburgh Pirates player Chris Duffy. This limited edition card is numbered to 75, making it a special and collectible piece for fans and collectors of sports trading cards.