3.5 mm Stereo jack plug to 3.5 mm stereo jack socket. Adaptors: 6.35 mm stereo plug to 3.5 mm stereo socket, 3.5 mm mono plug to 3.5 mm stereo socket, 2.5 mm mono plug to 3.5 mm stereo socket, 3.5 mm mono plug to 3.5 mm stereo socket.