The MFJ-332S is a 2-inch magnet mount with 12.5 foot RG58 coax to a quality SMA connector so you can screw your flexible rubber duck right into it.
This extra-strong magnet mount easily holds a lightweight rubber duck antenna. Set it on top of your car and suddenly you’ve got a great mobile rig out of your HT and rubber duck antenna. Get your handheld antenna out in the elements, in the air and avoid the shielding effect of your automobile.
It gets your antenna out where it can radiate freely and gives increased signal strength and reception performance by getting your HT antenna outside the car.