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# protocols

An array of protocols indicated in the ATR

```
var protocols: [NSNumber] { get }
```

## Discussion

Each element in the returned array is an `NSNumber` object containing an `NSUInteger` value corresponding to a member of the [`TKSmartCardProtocol`](/documentation/CryptoTokenKit/TKSmartCardProtocol) enumeration.

The returned protocols are ordered such that the default protocol is at index `0`, and any duplicate values are removed.

---

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