: A deep reddish, moderately strong, malty, complex Belgian ale.
Most commercial examples are in the 6.5 - 7% ABV range. Traditionally bottle-conditioned ("refermented in the bottle").
Westmalle Dubbel, St. Bernardus Pater 6, La Trappe Dubbel, Corsendonk Abbey Brown Ale, Grimbergen Double, Affligem Dubbel, Chimay Premiere (Red), Pater Lieven Bruin, Duinen Dubbel, St. Feuillien Brune, New Belgium Abbey Belgian Style Ale, Stoudts Abbey Double Ale, Russian River Benediction, Flying Fish Dubbel, Lost Abbey Lost and Found Abbey Ale, Allagash Double
You can view the complete style details on the BJCP website. The 2008 style guide is obsolete but there is a similar 2015 style that you can view below...