Check the listing for details. Heavy-Duty Barrel Spring Mounting Base [Chrome-Plated] [1/2" Mounting Hardware]. Condition: New. Listed at 18.99 USD. PROTECT YOUR INVESTMENT - Instead of slamming your whip into every low hanging tree branch, a spring base reduces the damage done by impacts by allowing the whip to bend and flex out of the way. FLEXIBLE - High speeds and corners can do a number on your whips and antennas, testing them to the limit of their flexibility. A sturdy spring base can take a lot of the stress of your equipment during hard highway or off-road use. HEAVY-DUTY - With a beefier 1/2" x 20 thread, this spring base is suitable for LED whip, fiberglass CB antenna, center load antenna, 102" whip, and so much more. MULTI-VEHICLE - Whether you drive an off-road ATV, an emergency vehicle, or a pilot car, a spring base is a practical and useful addition to any vehicle equipped with a large whip or antenna. DURABLE - Made from heavy-duty 6mm spring steel, this barrel spring base will not let you down and can handle even the largest LED whips and antennas