The next installment in Upslope Brewing Co.’s Lee Hill Series will be Barrel Aged Imperial Milk Stout, which as its name implies, is a 9.1 percent ABV imperial milk stout brewed with “premium malt” and lactose sugar before being aged in Leopold Brothers rye whiskey barrels for seven months before being canned.

“No matter where we are as a business, we remain steadfast in our exhilaration to maintain a legacy in innovation, collaboration, and experimentation,” said Matt Cutter, Upslope’s founder, in a press release. “This is the type of brewing where Upslope has laid its foundation. After tasting this beer for the first time, Volume 7 of the Lee Hill series is proving to be a rare keepsake.”

Barrel-Aged Imperial Milk Stout is the seventh release in the Boulder, Colo. brewery’s Lee Hill Series, which commemorates the original brewery location at Lee Hill in Boulder which is now used to produce small batch releases.

To date, there have been six other releases in the series:

  • Vol. 1: Barrel Aged Brown Ale, a 7.6 percent ABV brown ale aged for four months in Leopold Bros. rye whiskey barrels
  • Vol. 2: Wild Saison, a 6.8 percent ABV saison aged for seven months in red wine barrels and was brewed with both lactobacillus and brettanomyces
  • Vol: 3: Barrel Aged Imperial Stout, a 10 percent ABV imperial stout aged in Leopold Bros. Maryland-style rye whiskey barrels for four months
  • Vol. 4: Manhattan Style Rye Ale, a 10.4 percent ABV ale aged in first use Leopold barrels
  • Vol: 5: Belgian Style Quadrupel Ale, a 12.8 percent ABV quadrupel brewed with “a select strain” of Belgian yeast and traditional Belgian candi syrup
  • Vol 6: Wild Christmas Ale, a 9.2 percent ABV Belgian-style spiced dubbed brewery with brettanomyces and aged in Leopold barrels for 10 months
  • Vol 7: Barrel Aged Imperial Milk Stout, a 9.1 percent ABV imperial milk stout aged in Leopold barrels for 7 months

According to the brewery, 19.2 ounce cans ($10) of Lee Hill Series: Vol 7: Barrel-Aged Imperial Milk Stout will be released at an event on Feb. 4 at the Lee Hill tap room in Boulder, Colo. with a six can per person limit.