10k boost. Go to halfords buy some carb cleaner or even brake cleaner, its the same thing for less than a fiver.
Also this doesnt remove carbon. At best it gets rid of the fluff and the oil but if it removes carbon then I am brittney spears. Its hard enough to do with a wire brush in a drill and I will be fecked if a spray can do it.
Engien flush, a thin oil like solvent which is added to the oil and in theory removes and crap, again it doesnt remove everything. IT can also lead to oil leaks etc due to it removing oily gunge which is helping tired seals do their job.