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 5920-01-449-2172
NSN 5998-01-464-4017
NSN 5950-01-207-0929
NSN 6135-01-633-8502
NSN 5905-01-594-2937
NSN 5855-00-165-3093
NSN 6110-01-385-0955
NSN 5925-00-102-8010
NSN 6110-01-120-9705
NSN 2925-01-446-6976
NSN 4140-00-257-5215
NSN 5915-01-433-2405