This Polar Heart Rate Monitor is one of Polar's lower-priced models, with an MSRP of $89.95, but it has a number of attractive features. The monitor consists of a watch/computer and a coded transmitter, which minimizes interference from other electronic devices. It automatically determines the wearer's target heart rate zone, based on age, and will provide both a visual and audible alarm if the wearer is exercising either above or below that zone. The audible feature can be turned off, which I always do if I'm going to be wearing it in an exercise class. Although the unit is designed to determine a target heart rate zone automatically, it allows the user to define his minimum and maximum if he prefers. The target zone can be defined in beats per minute, which is the setting I use, percent of maximum heart rate, or a percentage heart rate reserve.

When the exercise function is activated on the wrist unit, the user's heart rate is measured, and the unit keeps track of the length of time the user has been exercising and the average and maximum heart rates for the exercise duration. The user has hands-free access to the training information while exercising simply by bringing the wrist unit close to his chest, which is a very convenient feature. Each session's summary is stored until the user's next exercise session, when it is then overwritten.

The wrist unit has a polyurethane strap, and the watch/computer back cover is stainless steel. The battery (CR2025) life of the watch/computer is estimated to be two years, based on the assumption that the user will be exercising 1 hour each day, 7 days a week. The watch can be set to display time in either a 12 or 24 hour format and features a date and day display and a backlight. It has an accuracy rating of ± 2 seconds a day, and I have had no reason to doubt this rating. Mine has kept exceptional time. The transmitter consists of a nylon and polyester strap with rubber tabs and a polyurethane buckle. It has a built-in lithium cell battery, rated at 2500 hours and for temperatures from 14?F to 122?F (-10?C to +50?C.) The unit is water resistant to 50 meters and can be used when swimming, but this particular model is not recommended for use when scuba diving.

My Polar FS3c has been both functional and durable. My biggest issue with it is that the batteries are not user replaceable, and when I had to send my unit into an authorized service center to have the batteries replaced recently, I found that the battery replacement cost more than I would have had to pay for a brand-new heart monitor with similar features (not a Polar model, however.) When this set of batteries wears out, I will shop for a monitor that has user replaceable batteries and one that allows me to enter my weight as well as my age and will provide me with information on calories burned. I would also prefer one that allows me to store the data for more than one exercise session, so that I can better track my progress.