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# characteristics

A list of characteristics of a service.

```
var characteristics: [CBCharacteristic]? { get set }
```

## Discussion

An array containing [`CBCharacteristic`](/documentation/CoreBluetooth/CBCharacteristic) objects that represent a service’s characteristics. Characteristics provide further details about a peripheral’s service. For example, a heart rate service may contain one characteristic that describes the intended body location of the device’s heart rate sensor, while another characteristic transmits heart rate measurement data.

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