Used sequential unit (found in trunk) relay for all 1970-73 Mercury Cougar, 4 total per car. Additionally this relay was used as a horn relay for 1965 Ford Mustang with generators; 1966 Lincoln Continental relay for moveable steering columns; 1969 and later Ford and Mercury full sized with speed control relay and power back window relay (on station wagons).
Ford Engineering # C4AZ-13853-A.
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