Hey everyone with small engines, this Mechanic in A Bottle is like magic in a 4oz bottle! If you've got a lawn mower, generator, chainsaw, or any small engine that's running rough or won't start at all, this stuff can save you a ton of time and money on repairs. It cleans out varnish and carbon deposits from your fuel system and carburetor without you having to take anything apart - just pour it in your gas tank and let it work its magic. It also absorbs water that accumulates in your tank, which is huge for preventing ethanol-related fuel problems. The formula actually revitalizes old gas and reconditions rubber and plastic components in your fuel system. You'll notice better performance too - on average about 10% improvement in fuel mileage and torque. It works with both 2-stroke and 4-stroke engines and treats up to 40 gallons of gas. Seriously, if you're dealing with hard starting, rough idling, or poor performance from your outdoor equipment, this additive is definitely worth trying before you pay for expensive carburetor repairs. It's saved me multiple trips to the small engine repair shop and gotten my equipment running smoothly again. Your lawn mower, generator, and other small engines will thank you for this treatment!