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 5920-01-097-0207
NSN 6645-01-238-8660
NSN 6145-00-873-4808
NSN 5935-01-508-4433
NSN 5930-01-592-2030
NSN 5905-00-115-5382
NSN 6150-01-622-3498
NSN 6105-01-255-4028
NSN 5920-01-503-7235
NSN 5999-01-429-8926
NSN 6150-01-611-2538
NSN 6135-01-648-0057