Enhanced Durability with M12x30 Thread: Our antenna spring base is designed with a robust M12x30 thread that offers exceptional strength and durability. It's perfect for use with various antennas, including LED whip antennas, fiberglass CB antennas, center-loaded antennas, and 102-inch whip antennas. This thread provides added stability and impact resistance, minimizing potential damage during use. | Universal Compatibility: This spring base is suitable for a wide range of vehicles and boats, making it highly versatile. As long as there is a 0.47-inch hole on the bottom of the vehicle or base for mounting screws with M12x30 thread, it can be easily installed. Compatible vehicles include UTVs, ATVs, trucks, go-karts, sand rails, ambulances, pilot cars, and more. | Premium Craftsmanship: Crafted from carbon steel, our spring base features a pot-bellied barrel spring design for increased flexibility and durability. It's further enhanced with a thick black powder coat finish that offers excellent resistance to shocks, water, and rust. The slick finish also makes it easy to clean. Stainless steel nuts and washers are included for added convenience. | Practical Addition for Various Vehicles: Whether you're driving an off-road ATV, an emergency vehicle, or a pilot car, this spring base is a practical and valuable addition. It is designed to accommodate large whip antennas or other similar accessories, enhancing the functionality of your vehicle. | Wide Application Range: This spring-loaded base is compatible with a variety of antennas, including LED whip antennas, fiberglass CB antennas, center load antennas, and whip lights. It can accommodate antennas with a minimum diameter of 0.448 inches and a maximum diameter of 0.465 inches, making it suitable for a wide range of applications.