12Dbi Gain Signal Booster 3M And Antenna Universal Holder For 3G/Gsm/Cdma Phone Provide better cell phone signal reception in those rural areas that everyone travels too, yet carriers do not build enough towers there Even in areas of poor network coverage, optimal reception can still be achieved by using a directional antenna with higher antenna gain. If the landline connection becomes interrupted (lines become clogged), the 3G/GSM network can provide you with an effective backup system. Rubber sucker base could be stick on the table or shield window firmly By connecting the 12dbi Signal Antenna directly to a telephone system you won't require a landline anymore