Octomore Masterclass 08.4 is an 8-year-old Scotch whisky produced by Bruichladdich. Distilled in 2009 and bottled in 2017, it was limited to 12,000 bottles. The whisky is aged 20% in virgin oak and 80% in first-fill American oak bourbon casks before finishing in European virgin oak casks that previously held Octomore 07.4. It is bottled at 58.7% ABV.