Lower mast clamp.
There is a Yaesu rotator for every aspect of communications. Amateur radio operators find Yaesu rotators indispensable for making difficult contacts possible. All Yaesu rotators are housed in weatherproof, die-cast aluminum enclosures and permanently lubricated for years of smooth, quiet operation. Unlike other rotators, which use noisy wedge brakes, Yaesu rotators have a quiet, reliable, gear-reduction breaking system.