From Stryker website:

"Stryker introduces the magnetic mount version of the powerful SR-A10 Antenna. This little gun will meet all your expectations b/c it is suitable to all kinds of radios, best in class & can combat any bad weather situations. It’s an ideal choice for cars, 4×4, jeeps or commercial vehicles.  Imagine 6 Gauge Solid Copper 100% Silver Plate Wire with the powerful magnetic base, you will only expect it from this Magnetic mount version.    Stryker SR-A10 is according to modern standards & needs. The load coil can be removed from the magnetic base easily. This will allow you to keep it safe  when not in use. Stryker SR-A10 is equipped with a powerful magnetic base of 5” diameter. This means this will not come off no matter how fast you travel. A Stryker SR-A10 MM antenna is an ideal choice for vehicles cruising at high speeds. "