Different types of chaplets for twentieth-century industrial iron sand casting. Each type has a special use: A–F are perforated sheet tin for heavy loads; I–M are for the heavier castings (tons); G–I are the most common types. From Palmer, R. H. 1929. Foundry Practice: A Text Book for Executives, Molders, Students and Apprentices. 4th ed. New York: John Wiley & Sons. http://archive.org/details/foundrypracticet00palm., 157, fig. 119.