This stud blocking diode can handle a very high amperage rating (75 Amps) and can be used on large generator units that produce lots of Amps. If this 75 Amp diode is more than you need, consider our 40 Amp diodes. Why is a diode necessary? All wind generator or solar panel applications require a diode. For 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 motor on the windmill from the battery bank and spin the motor when there is no wind. The motor would spin until the battery bank was completely drained.