Odell Brewing Co.has released the first packaged version of its Bourbon Barrel Stout since 2011.

Bull Proof is a 12 percent ABV imperial stout aged in freshly emptied bourbon barrels sourced from Fort Collins, Colo.-based Old Elk Distillery. The new stout is the latest addition to Odell’s Cellar Series, which is made up of beers that are made with the brewery’s pilot system, with some “brewed in the name of research, some are envelope pushers, and some are just for fun.”

“A bourbon barrel stout is, by design, an exercise in collaboration,” reads the beer label. “When Old Elk Distillery opened its doors less than a mile from our brewery, back of napkin sketches were traded, and after months of patience, this imperial stout is realized.”

According to a press release, Bull Proof Bourbon Barrel Stout is packaged in 12-ounce bottles and is now shipping in “very limited quantities” across Odell’s 16-state distribution footprint.

Update (Feb. 19, 2018) — This post was updated to include details on the release date and distribution information. It was originally published on Dec. 18, 2017.