This is a pair of brushed aluminum lights measuring ~44mm diameter, and ~71mm long. They come complete with the mounting stems and nuts as shown in the photos. They install with two wires and use single filament bulbs. These classic styled lights are for custom applications only, and for whatever reason, these do not have DOT rated for use as turn signals but there are surely a lot of them out there serving that purpose. ~10mm diameter stem, ~30mm stem length.