For recreational athletes. Get all the essential heart rate features with this good-looking & simple-to-use training computer. RS300X is compatible with S1 foot pod™ & G1 GPS sensor, so you can combine heart rate with speed & distance. Only then you can truly make sense of your training & be sure it's worth all the effort. * Helps you to train at the right intensity with personal training zones * Displays how many calories you've burned * Tracks your latest 16 training sessions & your last 16 weeks of training * Transfers training data to polarpersonaltrainer.com with optional Polar Flow Link™