There are two types of call transfer.

1) 'Blind' - when you transfer immediately without talking to the person you're transferring the call too e.g. if you're transferring to another call queue, or directly to someone's voicemail.

2) 'Attended' - when you have a chance to speak to the person you're transferring the call to e.g. if you're transferring to a colleague and you need to explain why you're transferring the call to them.

In the Webclient, you can simply choose which of these you intend to use. 'Transfer' for a Blind Transfer, and 'Att.transfer' for an Attended Transfer.