-- 2007 - 2008 - 2009 -- Cadillac DTS & Cadillac SRX AM FM Radio CD Player with Auxiliary Input -- DEALER UNLOCK REQUIRED!!! -- Part Number: 15948004 Compatible Part Numbers: 15877516, 25808216, and 25818943 Option Code: US8 / U2R This is for a 2007-2009 Cadillac DTS and SRX AM FM Radio CD player with Aux Input that has been professionally remanufactured. This radio has been cleaned, serviced as needed and thoroughly checked. The part number is 15948004 with option code US8 or U2R, so please make sure this is the correct radio for your vehicle. Appearance is great as pictured and the function is perfect! If you do not have one of the compatible part numbers listed above currently in your vehicle, it will likely NOT WORK. If you are unsure of your part number, give a Cadillac/GM dealer a call with your VIN and they should be able to provide you with the correct part number. They may look the same and have the same plugs but data streams may be different, not allowing them to code. For example, external amps are used in some cars and will not allow interchange, etc.