PC3-08-6 CT20UV05 Male ISO to Bullet End Car Stereo Radio Harness Adaptor. ISO Car Radio Harness Adaptor lead. An iso Car Radio Harness Adaptor lead allows you to install a car radio of your choice with out cutting any of the existing car wiring. All Car Radio Harness Adaptor Leads are ISO ended and will plug directly into most models of car radio. This harness is supplied with no vehicle connector, but bullets on the end that could be connected to bullets if fitted to the vehicle wiring.