Sometimes referred to as "Abt," the abbey quadrupel style is a product of Belgian monastic brewing. Like other abbey ales, these beers are now produced by many secular commercial breweries in addition to some of the "authentic" Trappist (real Belgian monasteries) brewers. These beers are quadruple fermented ales that offer the richest, strongest, and most complex flavors to be found among the Belgian abbey ales. These beers are dark red-brown to brown in color, can display relatively nice heads (despite the high alcohol level), and feature full and sometimes creamy mouthfeels. The flavors are highly imbalanced towards malty flavors (fruits such as plums, raisins, figs, even peaches are common, as well as chocolate and caramel), often contain yeasty tones (including the phenolic/spicey byproducts of fermentation), and feature no hoppy character. The alcohol levels of these special beers are typically in the 10% and higher range.