[Easy to install]: No drilling required. 1. Clean and dry the location where you need to attach the product. 2. Compare the installation location. 3. Peel off the product backing. 4. Attach the antenna to the product (if you don't need to attach the antenna, you can put the antenna in). 5. Press the product until it is firm. [Size]: Auto Cars Antenna Accessories size 6.69*2.75*2.75inch.To avoid inconvenience, please check the size before ordering to make sure this Roof Aerial Base AM/FM Radio Signal fits your antenna base. [Widely used]: Automotive Top Roof Aerials AM/FM Radio Signal Base is suitable for most cars with slightly curved or flat roof surface, shark fin shape design can replace the original long antenna, more beautiful and fashionable, enhance your car's class. [Shark Fin Antenna Feature]: Shark fin antenna is design to improve slope and reduce wind resistance, built-in pure copper antenna and chip, can better receive AM/FM signals, making the signal stable and powerful. [High Quality]: Car Antenna Cover is made of high quality ABS baked finish material, shark fin antenna is strong and durable, water, dust, exposure and sturdy for long term use.