Made for vehicles with a non-metal roof that uses a ground plane antenna. For best performance, mount the Ground Plane Disc on top of your roof and your antenna on top of the disc.

The Ground Plane disc can be mounted on the underside of the roof, but antenna performance may decline. 4 holes in the ground plane allow you to incrementally adjust the position of your antenna once it has been mounted.

6″ Diameter
Alloy construction
(4) 3/8″ holes