More About Sweet Rust Distilling Single Barrel. Cask Strength. Sweet Rust is an American take on the Independent Bottling concept that has propelled malt Scotch Whisky in the United Kingdom for generations. Our Vatting House concept is an attempt to find some of the most delicious whiskey and spirits casks from throughout Pennsylvania, the United States and around the world and offer them to our fans unadulterated — each bottle contains single barrel, cask strength spirit, undiluted and unfiltered. The best possible whiskey at the lowest possible price. And the worst-kept secret in the world of whiskey. Find out more at www.sweetrust.com.