0CC is the file extension added in 0CC-FamiTracker version 0.3.14.0 to distinguish between vanilla FamiTracker modules and those using the features exclusive in 0CC-FamiTracker.

0CC files are a superset of FTM files. If an 0CC module is known not to use any 0CC-FamiTracker features, it may be opened in official FamiTracker by selecting "All files (*.*)" in the Open File dialog, in the same way .ftm.bak files were opened. (although official FamiTracker is never able to produce backup files even if that option is enabled in the configuration menu)