Camel hair brushes are typically not made with camel hair.

At one time this description referred to the material used to produce the brushes, but it has since grown into more of a blanket term used to categorize a specific variety of paintbrush. These soft-bristled brushes with a rounded tip are commonly used in watercoloring, lettering, and tempera painting. Camel hair brushes are now manufactured using squirrel, goat, ox, and/or pony hairs, which is likely due to the reduced cost of raising such animals in comparison to hump-backs.
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