This is T20 7443 Error Free Load Resistor LED Decoder.
Use most when you met the Failure when your try to converted your original Halogen lamps to LED Lights.
The T20 7443 Error Free Load Resistors works as warning canceller, decoder, capacitor, or blinker rapid Flash Equalizer to ensure no error message for LED Light / Xenon HID Light to install in your car, such as the turn signal light, reverse light, tail brake light, headlight, daytime running light with T20 7443 housing adapter.