Body size (W x H x D) mm Length 40.5 mm x Width 40.5 mm x Height 11.2 mm Power source Rechargeable Charging time 2 hours Heart rate sensor Yes Compatible OS iOS 13.3 or later, Android OS 10 or later gps sensor Yes Incoming call notification function Yes Email notification function Yes Waterproof function Yes Pedometer function Yes Suica function Yes Blood oxygen wellness function Yes Sleep measurement function Yes Hands-free calling function Yes Dustproof function Yes Barometric pressure sensor Yes Calorie consumption measurement function Yes Voice assist function Yes Coaching function Yes Sedentary attention Yes Accessories Classic belt (s and l sizes), charging cable Basic Information Product name Smartwatch Fitbit Versa 4 Black FB523BKBK-frcjk Model number FB523BKBKFRCJK Manufacturer Fitbit (Go to manufacturer's site) Product code 10498595 Release Date: Sep. 29, 2022 Color Black Manufacturer Warranty 1 year