The carburettor cleaner fluid is a concentrate formula specifically for use with an ultrasonic cleaner, for carburettors, valves, fuel injectors, engine parts etc. It safely and quickly removes general grime and dulling, oxidation, carbon, petrol residue and grease etc. It works very well on alloys and aluminium castings, not only removing the physical dirt, but also it visually brightens dulling that occurs over time. Obviously it can't make a component look like it did when it first left the manufacturer's factory, but results are very impressive. The cleaning process won't damage, corrode or darken components. Safe on brass, aluminium and other sensitive metals. It is also safe with O rings. Mix the concentrate 1 part solution to 10 parts water (5 litre bottle makes 50 litre of working solution).