Polar's CS600X is the ultimate computer for riders who demand the most from their workouts. This informative powerhouse includes an altimeter that measures cumulative ascents and descents, interval timers and an interval measurement that records low-intensity fitness rate as well as resting rates. There are also visual and audible alarms that alert you when you've reached cadence-based or heart-rate based target zones. Plus, you can view your current, average and max speeds via the wireless speed sensor, estimated time of arrival, and have guided interval training with recovery measurements. And, you can transfer your data wirelessly to your PC, then plan, analyze and dial in your training with Polar's ProTrainer 5 software!