Bluemax signal booster 900 boosts voice signal for GSM network operators that are using 900Mhz telecom frequency.Please select right model from all our Bluemax booster models as per your requirements as all models are frequency-specific and serve for different frequency bands. Coverage area up to 2000 sq. feet (up-gradable to multiple rooms using accessories)., Works wirelessly with multiple cell phones user, network and data cards simultaneously., Immediately improve mobile signal quality. Suitable for hotel, restaurant, showroom, mall, shop, factory, house, tunnel, office, basement etc. Reliable, 100 % Protection and no side effects. Eco-friendly and no harm to human being. Technical person not required to installation since it's plug and play device.