Jawbone UP4
Tech specs 
Size220mm x 12.2mm x 3.0mm-9.3mm
Materialmedical-grade hypoallergenic TPU rubber strap; anodized aluminum casing (with less than 0.5% nickel); TiN-coated stainless steel clasp
ChargingMagnetic USB cable
BatteryRechargeable lithium polymer, 38 mAh battery
Battery lifeUP to 7 days
Water-resistanceWater resistant up to 10m
Weight29 grams
SensorAccelerometer, Bio-impedance, Skin Temperature, Ambient Temperature, NFC
DisplayThree single color LEDs - Blue for sleep; orange for activity; and white for notifications
Screen size
ColorsSilver, Black
Activity tracking 
Heart rateYes
Stress & recovery
UV exposure
Skin temperatureYes
Galvanic skin responseYes
Running features
Swimming features
Smartphone notifications
Other Pace, Respiration, Ambient Temperature. You can connect your UP4 band to an eligible American Express Card* for payments on the go at participating stores.
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