Laphroaig Quarter Cask Islay single malt Scotch whiskey takes its inspiration from the small casks often used for Scotch Whisky maturation in the 19th century. Double cask matured, first in oak barrels, then for a final period in specially commissioned Quarter Casks, as used two centuries ago. The result is a soft velvety sweetness, followed by intense peatiness so unique to Laphroaig.