Star Brite Star Tron Gasoline Additive.  I have a 10 HP Tecumseh engine on a 5000 Watt Generator that for the past two years had become difficult to start and wouldn't run without surging, back firing,etc.,  unless choked two notches . I'VE ALWAYS PUT STA-BIL IN THE FUEL TOO.  Now it does set for long periods without running though. Well after cleaning the bowl jets and still having problems I stumbled on this stuff. So ordered some, (what to lose ?) not much. I had emptied the old gas so put 1 gallon in the generator tank with the dose recommended (doubled) and started the engine. Still needed the two clicks of choke to run without surge etc. when started. I let it run for about two minutes and could hear a smoother sound coming from the engine. But it still needed one click of choke to run without surging. After 15 minutes checked and it ran silk smooth without any choke. Have checked it since and starts on the first pull too. I put it in a Robins 11 HP engine that was getting hard to start and it cured that within 5 minutes of running (cold starts too). Put it in my wife's old car and it runs smoother. Have 4 more small engines I will use this in too. I sound like a commercial but believe me this is worth every penny and cheaper than mechanics too. I have no doubt if used regularly in gas I won't have those problems again. I would recommend this to anyone for small engines, cars, etc. It really does what they say and the proof is in the engine performance.ADDENDUM: There are two concentrated formulas one 143XX for small engines and 930XX for Marine/Standard engines=(AUTO), (XX equals Oz in a bottle). The 930XX is a higher concentrate formula.  I received the 93032 (32Oz bottle) formula but was able to use it in small engines by reducing the amount per gallon and not wasting product that way. 10 Ml of 930(standard formula) is about the same as 1 Oz of 143(small engine formula) for 6 gallons of fuel. The company also says you can't overdose with this stuff. In other words if you put to much you just waste product not harm the engine. By the way 10 bottle caps full equal one Oz of product. Go to the Company web site and read how much to use and that way you will understand better what I have tried to say here. Take it from a 70 year old guy, This stuff is great. Everything I have put this in has increased the idle speed some .  Means water and crude has been removed . I put this in my new 2013 Kia Optima and two things happened, 1. increased idle speed and 2. increased the MPG 1 mile to the gallon. If you don't believe that that's OK I wouldn't and didn't when reading others say that. That car also expelled black crude from the exhaust pipes which is water vapor combined with carbon deposits caused by fuel burning cleaner. Decided we don't know what we are pumping from station storage tanks besides gas but the engines do. I've used this in 5 small engines, an older car, a truck, and a 40HP diesel tractor with improved performance from all of them. Great stuff.