4240-01-312-2772 (520-01-23R01)
4240-01-312-2772 is equivalent to manufacture part number 520-01-23R01. It is a dual-air breathing tube assembly and is classified under Federal Supply Class 4240 (4240 - Safety and Rescue Equipment), stocked for defense, aerospace, MRO, and industrial maintenance applications. This item is cataloged in the NATO supply system under 4240 - Safety and Rescue Equipment and is available through NSN-PARTS for U.S. government MRO, and commercial procurement.