Compatibility - Compatible with P71 Crown Victoria 3-3/4"/Compatible with Ford Crown Victoria, Ford Taurus, Ford Explorer, Dodge Charger, or Chevrolet Impala, Chevrolet Tahoe High Quality - Made of high quality materials,durable and long service life. Profile - Simply Place On Any Metal Surface Of Vehicle Such As The Roof Or Trunk.This Magnetic Antenna Will Not Transmit Or Receive. Easy to Install - Plug and play, easy installation.Professional installation is highly recommended.If you have any questions, please feel free to contact. Service - If you encounter any problems, please contact us and we will patiently solve all product related issues for you.