The GPS functionality of the device helps collect data about the route taken over long distances. In this endeavor, the device is by no means a simple contraption. It is powered by the SirfStar III GPS chip set that powers most capable GPS receivers. The curved surface of the watch-like device acts as a good antenna, and the high-resolution gray, back-lit display make the read out easy to see, even outdoors.The distance traveled during training are measured and maintained by the GPS device. Even when you train in completely unknown territories, the distances and route taken will be captured. The GPS data can be used for online mapping and route sharing with other athletes later.

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It is the training aids that make the device excellent. A heart rate monitor belt worn during training sessions communicate with the Garmin 305 GPS receiver wirelessly over a distance of up to about 10 feet. The athlete is completely free to move, except for this little extra sized sports watch like device on his wrist. Bicyclists and other athletes can also add on a motion and cadence sensor. This would help monitor if the rhythm of movement required is achieved during training. The data acquired includes heart rate, speed, distance, pace and calories burnt. Alerts available about time, distance, pace, and heart rate help ensure you train appropriately and without over-exertion.
Data can be stored within the device for up to 1000 laps. Auto lap, auto scroll and auto pause help monitor what you are doing on-the go. The bundled software provides the capability to download the stored data through a USB connection to analyze the session. The graphics/charting capability of the program allows you to derive all kinds of charts that help focus you on what exactly needs to be done.

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The battery supplied lets you go up to 10 hours per charge. This water resistant GPS is certified as per IPX7 standards, so working outdoors is not going to cause a problem.