According to
http://www.afcweb.com/faq_.html What's the difference between HCF and MC cable?
The difference between HCF and MC cables (as manufactured by AFC Cable Systems) is the grounding capabilities of the cable assemblies.
Type HCF cable has a green grounding conductor plus the armor/bond wire combination, thereby providing redundant or isolated grounding capability. HCF is a Type AC cable and is manufactured in accordance with U.L. 4.
Perhaps someone else manufactures an HCF cable that's type MC.
