The F3 had two internal antennas to maximize reception even when partially shielded by a hand or other obstacles, and a loud maximum volume for ringtones and loudspeaker to facilitate usage in crowded city environments or public transport. The unique default ringing mode vibrates silently for several seconds, then rings at modest volume, then with full volume. A vibrate-only mode and modes with fixed volume can also be set. To ease repairs or recycling, it can be opened by four Torx screws on the back.