Designed specifically for runners - The S-610i is the most powerful training tool available. With the new Infrared technology, you can download your files faster than ever before. Includes IrDa which allows transfer of data from a PC using infrared communication, now download directly to your PC without the use of a separate interface (must have the interface data port built into computer, or optional interface will be required). Get back from your workout and in seconds, the most in-depth performance analysis is right there on your PC (optional IR interface required). New enhanced Polar Performance software lets you look at your workouts every 5, 15 or 60 seconds. The 610i was designed for the athlete who trains with their head. Please Note: Your PC must have an infrared window in order to download without the use of a separate IR Interface. If not you will need a Polar IR USB Interface. Main Features: OwnIndexS™ - Measures your VO2 max OwnCal™ - Tracks nutrition expenditure OwnCode™ - Personal transmission feature Exercise Set™ - program the parameters of five key workouts (TZs, Timers, Recovery) Downloads data to your PC in seconds with the optional IR interface Includes IrDa which allows transfer of data from a PC using infrared communication. View heart rate as a % of Max hr 3 Target Zones and Timers Average and Recovery Heart Rate Interval Trainer Lap Splits with avg. Hr New ultra-thin chest transmitter Low battery indicator on watch receiver New, easy to use programming logic Full function stopwatch and everyday watch Stores 99 Files File Storage Capacity 60 sec. - Approx 100 hrs. 15 sec. - Approx 60 hrs. 5 sec. - Approx 22 hrs. (Storage capacity dependent on features in use) Polar Precision Performance Software