L.E.D. Tail Lamp Conversion Kit. For Cars Converted to Negative Ground. Also order flasher unit 17-1120. Applications: XK-140 Early XK-150 (single lens tail lamps) Later MK VII (not for cars with round tail lamps) All MK VIII Early MK IX (single-lens tail lamps) MK I There's simply no denying that cars are safer today by orders of magnitude. While you can't add air bags to your vintage Jaguar, you can upgrade the safety of your tail lamps with these nifty Light Emitting Diode (LED) tail lamp inserts. The difference in brightness is incredible and installation is simple. While these board-type LED conversions are more expensive than the Òbulb-typeÓ conversions, the difference is night and day. (Sorry, could not resist.) Two notes: These are polarity sensitive, so please order the correct type for your car. And, because LEDÕs draw so little power, you will need to replace your flasher unit for your turn signals to work correctly. Order part number 17-1120, which works for either positive or negative ground applications.