Finally, a GPS-enabled training device that isn't afraid of the water. The rugged Forerunner 310XT is the triathlete's indispensable training tool - a GPS-enabled, swim-proof trainer that tracks bike and run data and sends it wirelessly to your computer. This multi-sport device has up to 20 hours of battery life, tracks distance, pace and heart rate (optional), and goes from wrist to bike in seconds.