new_call, pressing a BLF / Extension / BLF (Server) key during an active call will put the active call on hold and a new call will be initiated dialling out to the configured number associated with the key.
blind, pressing a BLF / Extension / BLF (Server) key during an active call will blind transfer the active call to the configured number associated with the key.
attended, pressing a BLF / Extension / BLF (Server) key during an active call will put the active call on hold and initiate a new call to the configured number for attended transfer. User can complete the transfer as early attended or attended transfer via the "Transfer" key.
Web User Interface
Setup - Advanced - Behavior (Tab) - Keys (Section) - Quick Transfer to Speed Dial/Extension