I bought out the complete inventory of National Auto&Truck parts in the early 1980's and sold most everything but this piece was hiding behind the front door at my warehouse. I am pretty sure its for a small to mid size GM car. No part numbers are stamped into it but it has these: MD 4J DOT H82. If someone needs it it's a smoking good price for a new stamping! It's got 40 years of dust on it but it is perfect! Call if interested. Thanx