The Garmin Fenix 3 Sapphire is a rugged, capable and smart multisport training GPS watch. The Fenix 3 Sapphire has a real tough Stainless Steel band and Sapphire glass lens, which makes for a super tough and almost a 100% crack-proof watch face. With feature sets for fitness training plus feature sets for outdoor navigation, Fenix 3 is ready for any training activity and competition. Access to the Connect IQ platform allows customization of watch faces, data fields, widgets and activities. And, Fenix 3 is a thin, light multisport training GPS that won’t slow you down whether for training or every day use. The watch is packed full of features that tell you about your form and fitness. The first is the VO2 max estimator. When used with a heart rate monitor, Fenix 3 crunches data, including your running speed, beats per minute and heart rate variability to estimate the maximum volume of oxygen you can consume per minute. Track changes to your VO2 max to see your fitness gains and to compare with your peers. Other fitness metrics include recovery advisor with a recovery timer and recovery check, plus a Race Predictor, which estimates your ideal finish time based on your current VO2 max number.