1. Dart
2. dart:html
3. RtcDtmfSender
4. duration property

##### RtcDtmfSender class

1. Properties
2. canInsertDtmf
3. duration
4. hashCode
5. interToneGap
6. on
7. onToneChange
8. runtimeType
9. toneBuffer
10. track
11. Methods
12. addEventListener
13. dispatchEvent
14. insertDtmf
15. noSuchMethod
16. removeEventListener
17. toString
18. Operators
19. operator ==
20. Constants
21. toneChangeEvent

description

# duration property Null safety

int? duration

## Implementation

    int? get duration native;