The Solid-State Data Transfer Unit (SSDTU) and the Portable SSDTU replace the DTU-100 (P/N 1406-01-X), Portable DTU-100 (P/N 1407-01-X), DTU (P/N 1403-XX-X, 1405-01-X), Portable DTU (P/N 1404-01-X) and the Accessible Data Unit (ADU) (P/N 3060-0X-0X) in all Universal Avionics applications. Please refer to the Universal Avionics Specifications and Pricing Manual, or to the applicable Flight Management System (FMS) Installation Manual to identify the correct Part Number (P/N) for the project.