I bought the 3 litre unit for cleaning small engine carburettors. I’m pleased with the build quality, and the ease of use of the controls. Bill was also helpful in clarifying the UK safety and compliance of these machines. The cleaner was quieter than I had anticipated. It did a good job in concert with the Best Ultrasonic carb cleaning fluid, of cleaning all of the small internal passages and galleries of the carburettors, and made the process much easier than manual cleaning. My attached photo is of the first carb, after cleaning. It was previously coated internally with brown petrol varnish and residue. This machine is a great asset for my business.