The Airforce 4.1-2.5 KW turbine is independently-tested and CE-certified, utilities gearless, direct drive architecture, unique permanent magnet generator, carries industry standard 5-year warranty. Product Characteristics: high quality with low price; high efficiency( Cp-0.43) ; breeze start up-1.8m/ s; long lifetime; free of maintenance; light weight, easy installation; heavy wind resist( suvival wind speed-60m/ s) , low noisy; anti-rust, anti-corruption; damp-proof, water-proof, sand-proof.