Indicates whether the element has multiple instances or not.
Generators: .NET, .NET Framework, Android, Angular, Apple, Java
Level: Domain, Variable, SDT level node, SDT member
This property is available for:
1) SDT level nodes and SDT members:

2) Variables:

In both cases, you can achieve the same effect by selecting/clearing the IsCollection checkbox as well as by setting the Collection property.
3) Domains
Default value: False.
Note
If the variable corresponds to a Chatbot User Input, see Variable collection property behavior for User inputs.
This property applies only at design time.
Structured Data Type editor
Structured Data Type Properties