NOS Chev, Buick, Cadillac, Oldsmobile, Pontiac antenna relay 556511. There is no sign that this relay has ever been plugged in - no marks on the spade terminals. Did a mechanic think the relay was the problem with the antenna, but misdiagnosed the trouble.Should fit any General Motors division vehicle, with a power antenna, from 1977 through 1984. However, you will have to be the final judge of that. Sold as is, so check your application carefully. Thanks for looking.