An inverter system stabilizes the amount of voltage and frequency produced by a petrol engine driven alternator through the supply of "sine wave" electricity, with a distortion ratio of less than 3%. That's why Yamaha Inverters are the ideal power source when using precision equipment or micro-computer controlled electrical appliances. The EF2000iS has enough power to run a microwave oven, a camping fridge, a kettle or a television. It is fitted with a newly designed muffler and air filter to achieve super quiet performance and because of its advanced Noise Block sound reduction system you can have a conversation without having to raise your voice.