Unique training benefit feature provides instant feedback after your workout * Helps you train at the right intensity and improve your run with personal sport zones and the Running Index feature * Compatible with s3+ stride sensor for running speed and distance, cycling CS speed and cadence W.I.N.D. sensors and the G5 GPS sensor * Lets you share your training with friends and track your progress with polarpersonaltrainer.com, our free online training diary * Slim silicone wristband wipes clean and is designed specifically for female wrists