The TC-4100 Tower Tray Connector option is required when using the TT-4000 Optional Tower Tray. This connector allows the ability to help save time by supporting flexible media options. Workgroups can increase productivity by reducing time-consuming paper refills. Add the connector and tray to a compatible model to automatically print on letter or legal-sized paper without having to manually load paper trays for printing mixed-paper sized documents. Accessory Type: Tower Tray Connector; For Use With: Brother HL-EX470W, HL-L9310CDW, HL-L9430CDN, HL-L9470CDN, MFC-EX670W, MFC-L9570CDW, MFC-L9670CDN; Sheet Capacity: 520.