General 

The goal of this feature is to allow the implementer to set DTMF tones when transferring a call to an external number. This means that the call will be transferred without user action by the flow using the "Pass To Address" activity and after it is connected, the configured tones will be sent to the remote address.

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Another simple solution can be simple navigating the first step of the remote IVR 

Implementation 

On "Pass To Address" activity we have new options for selecting 2 additional parameters, the first is the delay that we need to wait from the time the call is connected until we start sending the DTMF sequence (one or numerous digits can be sent)
The second parameter is the sequence itself 

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