Connecting Smartphones(iPhone, Galaxy, LG, etc), MP3 player(iPod, Walkman, etc), Tablet (iPad, Galaxy, Fire, etc) to Stereo Receiver, speaker, amplifier and other RCA-enabled devices. Dual Shielding, Corrosion-resistant Gold-Plated connecters making the sound signal transmits with minimal signal loss. 2 RCA or 3.5mm could all be the audio input. In another words, it both work from 2RCA to 3.5mm & from 3.5mm to 2RCA. 3.5mm Male connector on one end and 2 Female RCA connectors on the other end.