Push to Talk calls may only be made with other Verizon Wireless Push to Talk subscribers, and only from the National Enhanced Services Rate and Coverage Area. For optimal Push to Talk performance, all callers on a Push to Talk session must have an EV-DO Rev. A-capable device and be receiving EV-DO service. A Push to Talk call is terminated by pressing END or will automatically time out after ten (10) seconds of inactivity. While you are on a Push to Talk call, voice calls received will go directly to Voice Mail. When you are on a voice call, you cannot receive a Push to Talk call. You cannot prevent others who have your wireless phone number from entering you into their Push to Talk contact list. Only one person can speak at a time during Push to Talk calls.  When using your phone keypad to make a Push to Talk call, you must enter the ten-digit phone number of the called party. Presence information may not be available for all Push to Talk contacts.  The timeliness of presence information may be impacted by the network registration status of a Push to Talk contact. Your Push to Talk service cannot be used for any applications that tether your phone to computers or other devices for any purpose. Push to Talk-capable phone and feature required.  Push to Talk subscribers cannot use Push to Talk or other data products and services (i.e. Picture Messaging, Mobile Web, Get It Now, BroadbandAccess Connect, etc) while roaming on other carriers' networks at this time.