One of Firestone Walker Brewing Co.’s most popular creations may be getting a brand new variant.

According to a label filed with the Alcohol and Tobacco Tax and Trade Bureau (TTB), that new creation will be Double Barrel Parabola, a 15.5 percent ABV imperial stout aged in both bourbon and hated whiskey barrels. Double Barrel Parabola will be packaged in 12-ounce bottles with 450 cases available when it is released.

As the name suggests, the base beer is Firestone Walker’s Parabola, a 14 percent ABV Russian imperial stout brewed with hallertau and Zeus hops along with nine different malts before being aged in a blend of bourbon barrels that have historically been sourced from Elijah Craig, Four Roses, Pappy Van Winkle, Woodford Reserve and Buffalo Trace.

An email sent to the brewery for additional information was not immediately returned.