Note on the range:

Wireless radio is not the same in each place test results, which depends on whether the surrounding tall buildings, you cannot make calls at the corner of architectural objects. If the building intercom populated region, the radio signal will be more affected if building less-intensive, although many results will still be good, because signals in buildings without intensive reflection and refraction, if dense and no way of reflection and refraction Oh! Pro radio not sure entirely how many kilometers apart from objects of different intensity of construction and architecture are also related to architectural objects, but also may be affected by radio frequency interference and other such similar, nearby electrical towers or other transmitters can influence! Parents, this is a powerful machine, General dense urban areas and there are no other wireless signal interference case, 2-4 km, 3-6 away from the sparse clearings for buildings in the suburbs can be! Floors can generally reach a 25-story building!

Note on distance must guarantee:

Walkie-talkies similar handsets, wireless signals are likely to be similar to different environments and signal interference and shielding, which could explain why can block wireless phones was the same way Oh! If you buy a phone if you ask the shopkeeper gave me a cell phone, and was on the phone to keep his phone at any place you can talk and listen very well, that the Treasurer must be going crazy mad

777S intercom: standard, there is a machine, a charger, a 1500 capacity battery, a back button, a description, and a lanyard.