40A, 600V stud blocking diode. This diode will work perfectly on many wind generator or solar panel applications. You should use a diode that is rated for 1.5 times the amount of your maximum amperage output. This diode is suitable for DC wind generators or solar panels generating 27 Amps or less, while the diode can handle up to 40 Amps. Please note, however, that it should not be subject to continuous duty at 40 Amps. All wind generator or solar panel applications require a diode. As an example, a diode will allow electricity to flow from your wind generator to your battery bank, allowing your windmill to charge your battery bank. It will NOT allow electricity to flow from your battery bank to your wind generator. If this happens, electricity would go to the generator on the windmill from the battery bank and spin the generator like an electric motor when there is no wind. It would spin until the battery bank was completely drained.