Single inheritance means that a channel variable will be inherited by created (spawned) channels, but not propogate from there to any other swawned channels. To follow our example above, if Alice sets a channel variable with single inheritance and calls Bob, Bob's channel will inherit that channel variable, but the channel variable won't get inherited by any channels that might get spawned by Bob's channel (if the call gets transferred, for example). To set single inheritance on a channel, preface the variable name with an underscore when giving it a value with the Set() application, as shown below.

exten=>6123,1,Set(_ACCOUNT=5551212)