4210-00-517-6904 (533721)
4210-00-517-6904 is equivalent to manufacture part number 533721. It is a winterization kit and is classified under Federal Supply Class 4210 (4210 - Fire Fighting Equipment), stocked for defense, aerospace, MRO, and industrial maintenance applications. This item is cataloged in the NATO supply system under 4210 - Fire Fighting Equipment and is available through NSN-PARTS for U.S. government MRO, and commercial procurement.