4610-01-553-0977 (IN. BB-3/4 IN. 20INBB34IN)
4610-01-553-0977 is equivalent to manufacture part number 20. It is a water purificatio filter element and is classified under Federal Supply Class 4610 (4610 - Water Purification Equipment), stocked for defense, aerospace, MRO, and industrial maintenance applications. This item is cataloged in the NATO supply system under 4610 - Water Purification Equipment and is available through NSN-PARTS for U.S. government MRO, and commercial procurement.