Rediform 7L721 Invoice Book, 5 1/2 x 7 7/8, Carbonless Duplicate, 50 Sets/Book Flexible cover and carbonless, numbered forms Part 1: white; part 2: yellow Our Carbonless books have a stop card to prevent write-through Manufactured with high-quality carbonless paper for a sharp and clear image reproduction, faithful to the original Pre-numbered to facilitate referencing and to increase control and security