5 Volt DC Power Supply for many newer SiriusXM Radios. This adapter will power your radio when it's in a PowerConnect Vehicle Dock (models XDPIV1, XDPIV2, SXVD1, SDPIV1, XAPV2, SXiV1). Compatibility is based on the Dock the Radio is in and not the Radio itself. When combined with the compatible PowerConnect Car Docks this adapter will also improve sound quality when using the radios built in FM Transmitter