Owners of 53-55 Corvettes had the option of buying from the dealer a promotional Key GM sold , many dealers gave them to new owners of Corvettes. Yes they had two keys but you used only one for the starter and trunk. The top pic. Is an after market set sold but they dint have the GM logo on the reverse side and the color was reversed .The original GM key is seen in bottom pic. A vary rare item to find today , usually you find the after market set for sale. Many were used in 56 up that did use the two keys .
The original GM key can bring $200.00 and up.
The original GM key can bring $200.00 and up.