Code 3 of 9, or code 39, is a symbology used widely in industrial applications. Dr David Allais invented this symbol and AIM USA developed the Uniform Symbology Specification. The Department of Defense (USA), the health industry and the automotive industry have also adopted Code 39 as their industry standard.
The Character Set is 0-9,A-Z,-,.,%,/,space,+,*.
Encodation - Five bars and four spaces are required to encode a character. Three of the nine bars and spaces are wide while the other six are narrow.
Start/Stop patterns - Always the character "*".
Code Type - Binary, varying length.
Human-Readable - Optional, though it is typically used.
Check Character - Optional, (modulus 43 calculation).
Encoded Information - Contingent upon data requirements.
Allowable Sizes - minimum "X" dimension: .0075 inches.
Wide to Narrow Ratio:
2:1 to 3:1 with "X" dimension > .020 inches.
2.2:1 to 3:1 with "X" dimension < .020 inches.
Allowable Symbol Height - The greater of .25 inch or 15% of the symbol length.
This is a Code 39 symbol encoding the data CODE39