6625-00-335-2553 (CE87157)
NSN 6625-00-335-2553 (NIIN 00-335-2553) is an observation window in Federal Supply Class 6625, Electrical And Electronic Properties Measuring And Testing Instruments — a transparent item of a predetermined size that permits unobstructed and undistorted view of a desired area. Manufacturer part number CE87157 (National Security Agency, CAGE 98230).
NIIN assigned January 1963; export Schedule B 3926.90.9988.