It provides signal amplification for the receiver. This would be great to replace a lost or broken one on a boat, van or car. It's got a magnetic base, so will securely attach without causing any damage to your vehicle. Prefect to give your GPS device a boost in signal and fast and better satellite fix. Color: Black Producat Name: GPS Antenna;Plug: SMA Male Plug;Power: 50W Gain: 27 +/- 2 dBi;Voltage: DC 3V-5V Frequency: 1575.42 MHz;Impedance: 50 Ohm;Bandwidth: 5 MHz Base Size: 4.8 x 3.8 x 1.7cm/1.9" x 1.5" x 0.7" (L x W x H);Cable Length: 3 /118" (9.8 Ft);Color: Black Material: Plastic, Metal;Weight: 69g Package Contents: 1 x GPS Antenna Only the above package content, other are not included. Note: Light and different displays may cause the color of the item in the a little different from the real thing. The measurement allowed error is +/- 1-3cm.