Pebbles-Lullaby Baby Gender Reveal Party Scratch Off Cards. At a reveal party, ask guests to mark their guess at the bottom of the card. Then let them scratch-off the gold sticker to see if they guessed correctly! This 4-1/4x3x1/2 inch package contains twelve cards, twelve scratch-off stickers, twelve blue stickers, twelve pink stickers and instructions. Acid free. Imported.