Standard Missouri Wind and Solar Falcon Wind Turbine Blade and Hub Set All parts are laser cut to exact tolerances for high quality operation and appearance All high tensile strength aluminum and 1018 steel construction will withstand severe weather conditions! Tested to 95 MPH winds The gull wing design has eliminated noise and cascade failure that all other aluminum blades suffer from. The more wind, the higher the RPM keeps increasing non-stop These extra large blades are designed for high torgue. 51" diameter for extreme high speed and torque that all high power PMAs require to put out any usable power Extremely large pitches on aluminum blades act like an anchor, and don't allow the blades to cut through the wind. Ours are low pitched for best performance