Akmaster:
I'm a little confused at the moment. You said...
" I am talking about the corrugated metal under the sheath of MC cable not AC or BX type. This is used in an industrial facility."
What 'sheath' are you refering to? Do you mean the type of MC cable that has an outer PVC jacket? That requires a connector that is specific to that cable, with the 'quick grip' fingers that bond the metalic sheath within that connector, but there is no 'bare ground' within that cable assembly.
I have a small piece here in the office, and one connector.
The connector has no info, other than a 'B' and UL. Jacket is marked '12/3 SUPER....; just partial, 2 hots, 1 neutral & grn ground. Neutral is #10, all are THHN /THWN.
BTW, Welcome to ECN.