This is probably the rarest dealer installed accessory offered in that era. Yenko dealership Novas and Camaros cars had them installed at the dealership on their muscle cars to help protect the theft of engine parts. I do not know the number that were sold and installed but how many of us car guys have even seen or heard of them. These are not mine but I know who has them listed and he has a hoard of nos 1970 camaro gm factory nos parts.We are all getting older and it is time for a lot of us to start liquidating spare duplicate parts. Check these on ebay and compare prices and availability. Rare parts and probably and even rarer market for them.