Garmin part number 010-10813-00. Mini-B USB connector to serial pigtail, with inline converter circuit. Use this cable for Fleet Management functionality on the StreetPilot 7000 series, 2720, 2820, c340, the Nuvi 300 series, and the Zumo 400 and 500 series.
Yellow is data out, white is data in, and black is ground. For Tracker2 and Tracker3 models excluding the T2-135 and T3-135, use yellow - pin 2, white - pin 3, black - pin 5 on a female DB9 connector. For the T2-135, T3-135 or cellular modems with DCE pinout, use white - pin 2, yellow - pin 3, black - pin 5 on a male DB9.
Both configurations are available as options below.