6665-01-209-0904 (5500-7500)
6665-01-209-0904 is equivalent to manufacture part number 550-075. It is a test calibration kit and is classified under Federal Supply Class 6665 (6665 - Hazard Detecting Instruments), stocked for defense, aerospace, MRO, and industrial maintenance applications. This item is cataloged in the NATO supply system under 6665 - Hazard Detecting Instruments and is available through NSN-PARTS for U.S. government MRO, and commercial procurement.