The double-walled design of these tumblers maintains your gin or whiskey’s temperature and prevents condensation for a smooth sipping experience. The double-walled design of these tumblers maintains your gin or whiskey’s temperature and prevents condensation for a smooth sipping experience. Viski is a passion project of home mixologists that happen to know a thing or two about product development. Back in 2012, they were looking to stock home bars with quality glassware and mixology tools. But they found that most of the products available were either too basic, or favored fashion while forgoing function. This gave them an idea - to make refined, functional bar tools and glassware for home mixology enthusiasts like them.