Fortinet FortiFone FON-370i Quick Start Manual page 9

Button Function
Voicemail — accesses voicemail and voicemail greetings.
DND — toggles do not disturb on and off.
Headset — toggles the headset on and off.
Transfer — transfers a call.
Hold/retrieve — places or retrieves a call on hold.
Redial — dials the last number dialed.
Mute — mutes and unmutes the microphone during calls.
Speakerphone — toggles the speaker on and off.
Using the Phone 6 FortiFone™ QuickStart Guide