# AspireUnionAttribute Properties

- Package: [Aspire.Hosting](/reference/api/csharp/aspire.hosting.md)
- Type: [AspireUnionAttribute](/reference/api/csharp/aspire.hosting/aspireunionattribute.md)
- Kind: `Properties`
- Members: `1`

Specifies that a parameter or property accepts a union of multiple ATS types.

## Types

- Name: `Types`
- Modifiers: `get`
- Returns: `Type[]`
- Source: [GitHub](https://github.com/microsoft/aspire/blob/bd20f904cde09ecb9c9ae5116a6f13614bf2d7c2/src/Aspire.Hosting/Ats/AspireUnionAttribute.cs#L60)

Gets the CLR types that form the union.

```csharp
public Type[] Types { get; }
```