The kit contains two disposable sensors, each of which is intended for up to 96 hours in typical continuous usage. The kit also contains 12 extra adhesive tapes, which should be replaced if they get dirty or if the adhesive is no longer sticking.
When inserted into a sensor, the indicator light on the chip will show you if the sensor needs to be replaced:
Sensor battery is low. Consider changing your sensor.
Sensor battery has no more power: You should replace the sensor.
1. Remove used tape from sensor
2. Attach new tape in the same direction as the used tape
3. Attach sensor to finger
4. Peel the remaining tape off backing and continue applying sensor per the instructions