5963-01-643-1683 (ECS-3953M-400-AU)
5963-01-643-1683 is equivalent to manufacture part number 70MC000188-001. It is a crystal controlled oscillator and is classified under Federal Supply Class 5963 (5963 - Electronic Modules), stocked for defense, aerospace, MRO, and industrial maintenance applications. This item is cataloged in the NATO supply system under 5963 - Electronic Modules and is available through NSN-PARTS for U.S. government MRO, and commercial procurement.