MIL-STD-2525 Symbol Identification Code
20 or 30 digit code which denotes a military symbol as specified in MIL-STD-2525 (source)
20 or 30 digit code which denotes a military symbol as specified in MIL-STD-2525 (source)
20 or 30 digit code which denotes a military symbol as specified in MIL-STD-2525 (source)