Prestige Distillers Turbo Yeast 18-20% £3.15

With this one can sometimes ferment large batches to 18% by adding 1/3rd of the sugar at the beginning and the rest after one week. This is normally impossible with high alcohol turbos because when the alcohol content reaches 14% or so, and the temperature is too high, the heat kills the yeast and the fermentation stops prematurely