Wheat whiskey is a style of whiskey defined by having a grain bill which consists primarily of wheat. The United States government only allows a product to be labeled "wheat whiskey" when the mash is composed of at least 51% wheat. Like other American styles, a wheat whiskey may be labelled as a "straight" if it is aged for at least two years in new, charred oak barrels. Although not true wheat whiskeys, some bourbon whiskeys are "wheated", that is because they use a certain percentage of wheat in their mashbills instead of the more common rye. Such brands include Cabin Still, Maker's Mark, Old Fitzgerald, Pappy Van Winkle's Family Reserve, Rebel Yell, and W. L. Weller.