Fits both 10" and 15" WindTrak models. Can be top or side mounted to extend your WindTrak vane away from masthead obstructions. The mount?s 13" (33 cm) aluminum arm lets your WindTrak easily clear most masthead running lights, antennas or electronic wind speed sensors. Gives the cockpit a better viewing angle of WindTrak. Comes with two brackets and all necessary stainless steel hardware to install on most mastheads. Accommodates offset angles to ?20 degrees.