From Whiskey Advocate: “Heavy Vapours, the latest Ardbeg Day release, was distilled without a purifier, marking a first in Ardbegs historythe distillery always uses a purifier, which makes it possible for its roughly 50 phenol parts per million whiskies to remain quite light, even with that high phenol content. Without the purifier, the resulting whisky is a heavier, smokier peat bomb, as the most highly condensed vapors were captured and bottled in the still (as opposed to being balanced out during distillation).”