Monitor your day to day activity levels with the Charge 2 from Fitbit. The Pure Pulse continuous heart rate tracker makes it easier to maximise workouts, better track calories burnt & get a reliable snapshot of your cardio fitness level while the all-day & auto-sleep tracking, lets you see how your whole routine adds up so that you can generate & maintain a more active lifestyle. The Charge 2 will really help you take your exercise experience to the next level. The multi-sport tracking records specific workouts so you can see real-time stats & view post-workout summaries on display. Enable Connected GPS during your runs to see stats like pace & distance on screen, & record a map of your route as you go. Smart Track technology will automatically recognise selected workouts & record them for you in the Fitbit app making sure you can reap the benefits of your exercise even if you forget to track it. As well as the active part of the day it will also monitor your sleep with regards to quality, hours slept & the number of times you wake up, with the aim that you can learn what helps you sleep & what makes you irritable during sleep so that restless nights can become a thing of the past. It also boasts a silent vibrating alarm to enable a more peaceful awakening at just the right time without waking anybody else up. Personalized guided breathing sessions will help you find a moment of calm in your busy schedule. By tracking your real-time heart rate with Pure Pulse technology these 2 minute or 5 minute sessions will give you prompts to help you relax & take 5. It is water resistant & able to sync wirelessly with your phone & other devices for excellent convenience & the Caller ID display linked with your phone will ensure you don't miss an important phone call mid-workout. Sizing tip: Small: 14-17cm Large: 16.5-20.6cm