DELCO PN 16227075 Active GPS Antenna, 5V Powered, with 10 foot RG-174 cable, terminated with right-angle SMB connector. These work great with the GARMIN portable units, by changing the plug to a BNC male. Probably with any other unit that supplies 5V to the antenna. About 2.5 inches in diameter, and .5 inches thick. Magnetic mount.