Back before the days of the electric door, porcelain advertising door pulls (and pushes) were a good way to get your product noticed by hungry or thirsty consumers. Some of the rarest and most valuable door pushes are from little known or now-defunct brands. But larger brands like Coca-Cola, 7-up, Copenhagen, Sunbeam bread, Canada Dry and Vicks also made push and pull signs, which are today sought by collectors. As with all signs, condition is paramount.