Duster Rear-Defroster/Defogger?
On the 73, they offered 2 types.
H31 Fan with blower--N/A with fold-down rear seat.
G01 Electric grid--Dart Sport only
My father had the blower type in his 68 Coronet. Sorta useless because the car had A/C.
http://www.hamtramck-historical.com/images/dealerships/DealershipDataBook/1973/73_Dart0019.jpg
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