General Info and Specifications
Sensors
Fitbit Charge 3 contains the following sensors and motors:
l A MEMS 3-axis accelerometer, which tracks motion patterns
l An altimeter, which tracks altitude changes
l An optical heart-rate tracker
Materials
The housing and buckle on Charge 3 are made of anodized aluminum. While
anodized aluminum can contain traces of nickel, which can cause an allergic reaction
in someone with nickel sensitivity, the amount of nickel in all Fitbit products meets
the European Union's stringent Nickel Directive.
The Fitbit Charge 3 classic band is made of a flexible, durable elastomer material
similar to that used in many sports watches.
Wireless technology
Charge 3 contains a Bluetooth 4.0 radio transceiver and Fitbit-Pay enabled trackers
contain an NFC chip.
Haptic feedback
Charge 3 contains a vibration motor for alarms, goals, notifications, and reminders.
Battery
Charge 3 contains a rechargeable lithium-polymer battery.
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