A single letter or numeral designed for use in marking a sheet of x-ray film for identification at the time of exposure.
NSN 6320-01-441-2438
NSN 5998-01-217-4919
NSN 6150-01-134-8462
NSN 5935-01-417-1004
NSN 6150-00-248-3866
NSN 5985-01-297-8827
NSN 5985-01-106-3003
NSN 5835-01-096-8570
NSN 5895-01-423-8160
NSN 5960-01-129-2509
NSN 6685-00-879-6137
NSN 6645-00-483-7044