For the artist (or any office) in need of a long lasting and versatile ink roller the Martin Yale Ink Roller for 930A and 931 in both black ink and tri-color ink is the perfect solution. Either one of the rollers can also be used with the Widmer Check Signer as well! If you are looking to get the most out of your ink rollers, put the "super flow" Martin Yale Black or Tri-Color Ink Rollers to the test. You'll be amazed at the quality of your images and enjoy the option of purchasing either the black ink roller or tri-color roller to accommodate all of your needs. Martin Yale is the name artists and all offices trust for long lasting, superior image transfers. For the best in quality and superior image transfer choose Martin Yale Ink Rollers in Black or Tri-Color for 930A and 931.