SODIAL(R) Magnetic Base GSM GPRS Network Signal Antenna 7dBi 900/1800 MHz 3 Meters This antenna is suitable for car, trucks, boats or other vehicle use. It improves cell phone voice and data reception, adding bars of signal to your phone and increased data transfer speeds. It also helps prevent dropped calls. It doesn't require a direct connection to your phone, but rather works wirelessly. It can also work for multiple users at the same time.