WHAT WILL MY MILEAGE GAIN BE? 
We have that question frequently asked. The fact is the answer to that question cannot properly be answered without stipulation. We might add, if one does so— we will be polite here— he may be ignorant to the real extenuating facts. First of all, supplemental hydrogen induced into any engine will not produce effective results UNLESS the engine is in VERY GOOD running condition. This means if your engine has ANY of the following problems: piston rings and/or valve(s), engine miss, check engine light on, oil burning consumption, unusual smoke emitting from exhaust and/or breather system, or overheating, or has not been tuned according to factory recommendations, DO NOT expect any fuel mileage improvement. And don’t install anyone’s HHO system until it is rectified by a professional that does mechanical work for a living and has ASE (Automotive Service Excellence) certification credentials. Simply stated, HHO is not a fix-all; but it is a proven fact that supplemental hydrogen reduces engine emissions and increases fuel economy on average by 30%. Scientific documented proof of this fact can be read on our website by searching Google: “Does supplemental hydrogen really work” and read the scientific documented facts from expert engineers who have conclusively studied it. However, supplemental hydrogen must be installed properly and the engine and its computer, where applicable, must be properly tuned for each application to accommodate the HHO induction. Placing any kind of supplemental hydrogen generator system onto any engine, without addressing the aforesaid, will yield little or no fuel mileage improvement. And if anyone leads you to believe otherwise, you will inevitably be rudely awakened.
About LaBella's Enterprises:
See “feedback” and “about” links on our EBay store agl0002 @
https://www.ebay.com/str/hhoproducts
Google:"supplemental hydrogen testimonials"