The Davis Instruments WindTrak AV Antenna Mount Wind Vane is a compact and efficient wind indicator designed to mount directly onto most whip antennas. Featuring a sapphire jewel suspension bearing and low-inertia 15" vane, it delivers accurate wind direction readings even in light air while minimizing masthead clutter, weight, and windage. Reflective tacking arms improve visibility, and the low-friction Teflon® bearings ensure smooth performance for reliable sailing or cruising navigation.