Fancy beer fans should look forward to a new release from 10 Barrel Brewery.

Rose Bois Grand Cru is a Belgium inspired wild sour ale brewed using two wild strains of yeast.

Part of the Bend, Ore. brewery’s Fancy Beer Series, this wild sour is aged for three years, giving the beer credence as the term grand cru is applied to, ‘a wine of the most superior grade.’ Available only in 750 ml bottles, this sour is a sturdy 7.4 percent ABV created by brewer Jimmy Seifrit.

A label filed with the Alcohol and Tobacco Tax and Trade Bureau (TTB), explains some of the background on the beer:

Inspired by old school Belgian Sours, this new brew too Jimmy three years to age to perfection. Using two types of wild yeasts, this convention will take your senses on a wild trip through earth and time.

The brewery responded to an inquiry about more details, but has not responded with said details.