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  "identifier" : "/documentation/TelephonyMessagingKit/MMSPartContent/MMSCustomHeader",
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  "title" : "MMSPartContent.MMSCustomHeader"
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# MMSPartContent.MMSCustomHeader

A structure that defines a custom header as a key-value pair.

```
struct MMSCustomHeader
```

## Overview

TelephonyMessagingKit exposes custom headers in case a message needs
to include them in an MMS message.

## Topics

### Accessing header properties

[`let key: String`](/documentation/TelephonyMessagingKit/MMSPartContent/MMSCustomHeader/key)

The key for the custom header.

[`let value: String`](/documentation/TelephonyMessagingKit/MMSPartContent/MMSCustomHeader/value)

The value of the custom header.

### Encoding and decoding

## Relationships

### Conforms To

[`Decodable`](/documentation/Swift/Decodable)

[`Encodable`](/documentation/Swift/Encodable)

[`SendableMetatype`](/documentation/Swift/SendableMetatype)

[`Sendable`](/documentation/Swift/Sendable)

---

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