Hy-Power Diode allow motor homes or RVs to power the lights on the tow vehicle without power feedback.
Diodes used to tie into the towed vehicles brake light, running light and turn signal wiring.
Tail Light Isolating Diodes. Diodes only allow electrical current to flow in one direction - from the motorhome to towed vehicle's taillights. It prevents any electrical feedback and the damage it may cause to the electrical components.
Replace an old/broken diode. A simple splicing into existing harness by just taking off the old spade connectors and replacing it.