4810-01-394-4811 (80041-1)
4810-01-394-4811 is equivalent to manufacture part number 20003. It is a valve opening indicator and is classified under Federal Supply Class 4810 (4810 - Valves, Powered), stocked for defense, aerospace, MRO, and industrial maintenance applications. This item is cataloged in the NATO supply system under 4810 - Valves, Powered and is available through NSN-PARTS for U.S. government MRO, and commercial procurement.