Faces must be parallel to within 0.010 in
A transparent item of a predetermined size that permits unobstructed and undistorted view of a desired area. It may include a frame, have reference markings, grid lines and may be heat strengthened and/or tinted. It is generally used where safety, security, and/or the restriction of foreign matter are required, such as the visual examination of the inside of pressurized tanks, liquid sights, controlled liquid flow, and inspection of equipment enclosed in a housing. See window (as modified); scale, cathode ray tube; scale, plotting; window, metal; window, wood; and window panel, aircraft.
Classification: Pressed or molded glass articles, wired or not, for building or construction;leaded glass windows etc; formed multicellular or foam glass
NSN 2925-01-033-0141
NSN 4140-01-205-0197
NSN 5998-00-884-6254
NSN 6620-00-006-6418
NSN 5975-00-600-5847
NSN 5985-01-528-8001
NSN 4140-01-007-7992
NSN 5915-01-430-4386
NSN 5895-00-565-6906
NSN 7035-00-185-8683
NSN 5945-01-597-7568
NSN 6220-01-396-0916