---
title: HMCharacteristicTypeSerialNumber
framework: homekit
role: symbol
role_heading: Global Variable
path: homekit/hmcharacteristictypeserialnumber
---

# HMCharacteristicTypeSerialNumber

The serial number of the accessory.

## Declaration

```swift
let HMCharacteristicTypeSerialNumber: String
```

## Discussion

Discussion The corresponding value is a string.

## See Also

### Deprecated characteristic types

- [HMCharacteristicTypeManufacturer](homekit/hmcharacteristictypemanufacturer.md)
- [HMCharacteristicTypeModel](homekit/hmcharacteristictypemodel.md)
- [HMCharacteristicTypeFirmwareVersion](homekit/hmcharacteristictypefirmwareversion.md)