Mark, I can't give you a name right off the top of my head, but you can use steel fittings with the aluminum if you have no choice and are not in severe corrosive areas
344.14 Dissimilar Metals
Where practicable, dissimilar metals in contact anywhere in the system shall be avoided to eliminate the possibility of galvanic action. Aluminum fittings and enclosures shall be permitted to be used with steel RMC, and steel fittings and enclosures shall be permitted to be used with aluminum RMC where not subject to severe corrosive influences.
Roger
