The XM-EXT50 antenna extension cable is a single 50' coaxial cable with single SMB connectors (without the plastic FAKRA-type plastic housing) on each end. The extension cable is equipped an in-line signal amplifier (10dB gain) on one end with a weather-resistant rubber boot. The other end plugs directly into single-input Sirius Satellite Radio receivers. Note: For connections to dual-input XM receivers, the Terk XM-SP dual-input splitter (item # 209XMSP), or the American International XM-1DAS (item #003XM1DAS) is required.