Back to the Future 40th Anniversary Time Circuits Ingot"First, you turn the time circuits on." The equipment used to tell the DeLorean where (or rather, when) you want to go to, the time circuits were integral to the time machine and one of Docs ingenious inventions. This limited edition ingot depicting the time circuits display measures 90 x 56. 5mm and is limited to 1,985, celebrating 40 years since the release of Back to the Future. Its individually numbered to the reverse and comes with a display