... 4 yards of the single number.The system also provides up to 32 automatic channel selection, can provide 32 pairs of users ... gain control, voice size does not vary with distance and phone number change.4, super call function: all calls, group calls, ... output power: 0-35W (adjustable)In 9, the channel number: 3210, maximum network number: 12811, installation: wall typeNote: when used outdoors, with ...