Stereo Antenna Harness Adapter for Installing a New Radio Into a Hyundai, Elantra and Sonata, 2009, 2010 Antenna adapter for installing a new Radio into a HYUNDAI ELANTRA and SONATA 2009, 2010 CarXtc adapter plugs directly into the antenna wire beyond the radio found in a ELANTRA and SONATA Plugs directly into your vehicle radio antenna harness behind the factory radio. Antenna adapter is needed for your HYUNDAI ELANTRA and SONATA 09, 10 If installing an FM modulator you will need this and the reverse antenna adapter