These highly opaque, lightfast and waterproof chalk markers are effective on surfaces such as glass, plastic, metal, wood and stone. These prominent liquid chalk markers produce a chalk look without a chalk mess, are a valve-action and work exceptionally well on chalkboards and whiteboards and can be removed using glass cleaner. Mainly used in pubs, bars and restaurants, with some classy artwork, these markers can make your business stand out from the rest!