![Amazon.com: WHOOP Battery Pack 4.0 – Portable, Wearable, Water-Resistant Charging Component 4.0 Wearable Health, Fitness & Activity Tracker, Onyx : Electronics Amazon.com: WHOOP Battery Pack 4.0 – Portable, Wearable, Water-Resistant Charging Component 4.0 Wearable Health, Fitness & Activity Tracker, Onyx : Electronics](https://m.media-amazon.com/images/I/71pk-It2aAL._AC_UF350,350_QL80_.jpg)
Amazon.com: WHOOP Battery Pack 4.0 – Portable, Wearable, Water-Resistant Charging Component 4.0 Wearable Health, Fitness & Activity Tracker, Onyx : Electronics
![Just got the 4.0. It feels more comfortable immediately. Smaller than the 3 but about as high off your wrist. : r/whoop Just got the 4.0. It feels more comfortable immediately. Smaller than the 3 but about as high off your wrist. : r/whoop](https://i.redd.it/g1tu85hncd481.jpg)
Just got the 4.0. It feels more comfortable immediately. Smaller than the 3 but about as high off your wrist. : r/whoop
![Amazon.com : WHOOP 4.0 with 12 Month Subscription – Wearable Health, Fitness & Activity Tracker – Continuous Monitoring, Performance Optimization, Heart Rate Tracking – Improve Sleep, Strain, Recovery, Wellness : Sports & Outdoors Amazon.com : WHOOP 4.0 with 12 Month Subscription – Wearable Health, Fitness & Activity Tracker – Continuous Monitoring, Performance Optimization, Heart Rate Tracking – Improve Sleep, Strain, Recovery, Wellness : Sports & Outdoors](https://m.media-amazon.com/images/I/71GIHskfSCL._AC_UF1000,1000_QL80_.jpg)
Amazon.com : WHOOP 4.0 with 12 Month Subscription – Wearable Health, Fitness & Activity Tracker – Continuous Monitoring, Performance Optimization, Heart Rate Tracking – Improve Sleep, Strain, Recovery, Wellness : Sports & Outdoors
![Amazon.com : WHOOP 4.0 with 12 Month Subscription – Wearable Health, Fitness & Activity Tracker – Continuous Monitoring, Performance Optimization, Heart Rate Tracking – Improve Sleep, Strain, Recovery, Wellness : Sports & Outdoors Amazon.com : WHOOP 4.0 with 12 Month Subscription – Wearable Health, Fitness & Activity Tracker – Continuous Monitoring, Performance Optimization, Heart Rate Tracking – Improve Sleep, Strain, Recovery, Wellness : Sports & Outdoors](https://m.media-amazon.com/images/I/71CQ6esBqFL._AC_UF1000,1000_QL80_.jpg)
Amazon.com : WHOOP 4.0 with 12 Month Subscription – Wearable Health, Fitness & Activity Tracker – Continuous Monitoring, Performance Optimization, Heart Rate Tracking – Improve Sleep, Strain, Recovery, Wellness : Sports & Outdoors
![Amazon.com : WHOOP 4.0 with 12 Month Subscription - Wearable Health, Fitness & Activity Tracker and Ultra-Soft SuperKnit Accessory, Freedom : Sports & Outdoors Amazon.com : WHOOP 4.0 with 12 Month Subscription - Wearable Health, Fitness & Activity Tracker and Ultra-Soft SuperKnit Accessory, Freedom : Sports & Outdoors](https://m.media-amazon.com/images/I/81uOIyIwyqL._AC_UF1000,1000_QL80_.jpg)