If the CS600 doesn't tell you, you probably don't need to know.
The Polar CS600 with Power Cycling Heart Rate Monitor gives you complete control over the planning, monitoring and analyzing of your cycling and training. Monitor your target heart rate and calories with the wireless ECG sensor during your workout, and clock your times with an automatic lap recorder that logs up to 99 laps. When you get home, hook up the CS600 to Polar's web site or upload to the Polar ProTrainer 5 software (sold separately) to analyze your data and compare to previous workouts. Cycling functions include distance, speed, altitude, ascent/descent, calorie consumption, ETA, and incline measurement. The speed sensor installation accommodates different fork shapes, and the unit has a multifunctional handlebar/stem attachment. The CS600 also features most basic watch functions and three different target heart rate zones with audible and visual alarms.
This is the best device on the market for a cyclist who wants every possible piece of data on heart rate mixed into their cycling data. The altimeter actually works as well (but only on the bike - it doesn't stay on if you're off of the bike so don't try to use it climbing or skiing). The incline measurement is also a cool feature. The bad: the power monitor functions by sensing tension on the chain (in basic terms) and doens't work. If you're looking to really train with power, this won't cut the butter as sometimes it's off by several hundred watts over an interval.