The KIX barcode (Klant index) has nothing to do with breakfast cereal, but is used for mail sorting by the postal service of the Netherlands, Koninklijke TNT Post (Royal TNT Post). (If you use that "TNT" name as a launching point for jokes about blowing up post offices, you'll probably get a visit from government agents in the current political climate.)
This sort of bar code system is regarded as "four-state" because there are four types of bars, classified by presence of ascenders and/or descenders. This sort of system is transcribable using DAFT notation. These sorts of bar codes are used by a number of countries in their postal systems, though the specific symbologies by which they encode characters can vary. The KIX system encodes alphanumeric characters, and is a slight variant of the Royal Mail 4-State system, omitting the start and end symbols and checksum.
- Some official downloads (site is in Dutch, and has a very annoying interstitial warning about cookies that takes forever to dismiss and move on)
- Stimulsoft reporting software now boasts about supporting this bar code format
- KIX bar code font