Our Hydrogen Generating Machines are the highest quality top of the line technology available. The SPE-PEM electrolysis plates are manufactured by Dupont in the USA. There are cheaper Hydrogen Generating Machines on the market that produce toxic byproducts. We only carry products that are safe and that use Platinum coated Titanium electrolysis plates. These plates do cost more then the cheaper ones, but it is important to use these so toxic metals like molybdenum, chromium, and nickel are not leeched into the water.