4820-01-539-4418 (4121-007-01)
4820-01-539-4418 is equivalent to manufacture part number 4121-007-01. It is a oxygen syste safety relief valve and is classified under Federal Supply Class 4820 (4820 - Valves, Nonpowered), stocked for defense, aerospace, MRO, and industrial maintenance applications. This item is cataloged in the NATO supply system under 4820 - Valves, Nonpowered and is available through NSN-PARTS for U.S. government MRO, and commercial procurement.