Transfer belt installation is recommended every 100,000 images. The Lexmark Optra C710 Transfer Kit contains a replacement transfer belt and transfer roller that work together to ensure vibrant color printing for up to 100,000 images. For use with the Lexmark Optra C710, C710n and C710dn color printers and the OptraImage C710sx. Yield: * Up to 100K images. One 4-color page = 4 images.