An enhanced version of Code 39 that supports the full ASCII character set through special shift characters. Each extended character is represented by two Code 39 characters ($, /, %, + prefixes). While more versatile than standard Code 39, the extended version has lower density and requires careful implementation.

Key Features

Character Set: Full ASCII 128 characters
Density: Very low (double width for extended chars)
Check Digit: Optional modulo 43 checksum
Applications: Specialized industrial tracking