1、Applicable Models: LED whip light spring mount for LED whip antennas, fiberglass CB antennas, center load antennas, whip lights, etc. Suitable for minimum diameter 0.448inch, maximum diameter 0.465 Widely Applicable: Spring loaded base for LED whip antennas, fiberglass CB antennas. 2、M12x30 Thread: The spring loaded base allows the antenna to flex, thus minimizing damage from impact. Adopts stronger M12x30 threads, suitable for LED whip antennas, fiberglass CB antennas, center‑loaded antennas, 102inch whip antennas and so on. 3、High Flexibility: High speeds and curves can test your whip and antenna to the limit of its flexibility with a lot of tests. The sturdy spring loaded base can withstand a lot of stress on your equipment during hard highway or off road use. 4、Universal to Use: Suitable for most vehicles and boats, as long as there is a 0.47inch hole on the bottom of the vehicle or base for mounting screws (M12x30 thread), such as UTVs, ATVs, trucks, compatible with go karts, sand rails, ambulances, pilot cars and more. 5、Practical Accessories: Whether you drive an off road ATV, emergency vehicle or pilot car, the spring base is a practical and useful addition to any vehicle equipped with a large whip or antenna. 6、Fine Crafted: Carbon steel with pot bellied barrel spring for added flexibility and durability, baked on thick black powder coat finish for excellent shock, water and rust resistance, slick surface for easy cleaning, comes with stainless steel nuts and washers and more.