Spar-Fly™ Wind Vane (1310) by Davis Instruments®. Spar-Fly combines needle bearing balance, high impact plastic, and marine grade metals for unsurpassed sensitivity and durability. Spoiler holes in the vane reduce lift and increase accuracy. Spar-Fly is unaffected by angel of heel. Easily seen from the deck because of its V-shaped silhouette and bright red color. Weighs only 1.25 oz. (35 g).