I received this as a gift and have never used it. Size: Wrist: 21cm, 7g Arm: 34cm, 9g Chest: Minimum 57cm, Maximum 85cm, 34g Pod: 11g Measurement Accuracy: 99.4% accuracy using a chest ECG sensor, equivalent to equipment used by medical professionals. 95% accuracy using wrist and arm PPG sensors. Connectivity: Bluetooth ANT+ Durability: Waterproof: 10m depth Battery: Charging interval: 3-6 months *Depending on usage. Other: Stores up to 36 hours of exercise data. Requires iOS 12.0 or later or Android 6.0 or later to use the app. [Standard Accessories] ・MZ-Switch Body ・3 straps for chest, forearm, and wrist ・USB cable ・Start Guide ・Dedicated pouch Please note that this item is also listed on other sites, so please understand if it is sold out. Returns are not accepted.