This is a point to multi-point link with additional wireless cards and antenna for a backbone connection. Such links are useful when creating a WISP infrastructure, for example you have main Internet source with 5 GHz base station and lots of 2.4 GHz clients in various sides of the city. Such kits can be but in localized parts of the city and contain 2.4 GHz omnidirectional antenna and 5 GHz directional antenna to main base station.