Ultra is the parts brand name for electronics specialists Nagai Denshi. Being located Kanagawa Prefecture Nagai Denshi has been in operation since 1954. Most notably known for Ignition electronics and wires along with earthing systems they also have a nice selection of other niche electronic parts. Ultra has an extensive lineup of vehicles that they support for their Plug Cords providing enhanced performance and efficiency to just about any Japanese vehicle still on the road.