BTW, here are some pictures of my Trail-Tech HID and the rest of my setup (including BatterySpace 4.5 AH 14.4v NiMH battery)
http://www.hauntedfrog.com/gallery2/...g2_itemId=2701

NOTE: the rather complex bit, the voltage regulator, is only necessary because my battery is 14.4v, which is over spec for the HID. If used with a 12V pack, no regulator would be necessary since such a pack will put out a max of about 13.8V and the HID is rated to 14.8v. My 14.4v puts out nearly 16V for over an hour when freshly charged, so the regulator is necessary.