The CS 300 has a wireless sensor that provides current, average, and maximum speeds. It is easy to install and has an aerodynamic design. It tracks the cycling workload as kcal/h and kcal/km. With this feature you can foresee your calorie expenditure and secure sufficient intake on a long ride. It has estimated time of arrival which enables you to foresee the time of arrival based on your cycling speed. Also allows transfer exercise data from wrist unit to Polar Personal Trainer web service via Polar WebLink (SonicLink/Infrared).