The stud washer is a very important part of any CB antenna stud. The stud is the mount that holds your antenna onto your mount, and the junction for your coax cable. Most studs are composed of the top stud nut, some metal washers, the isolation washer (shown above) then your mount, and finally the bottom of the stud. These isolation washers keep your antenna from shorting to ground. Without these your system will work very poorly and can damage your radio. Make sure your antenna studs have washers!