Ham’s F-12, was originally formulated as a synthetic, serum-free media for the culturing of single-cell Chinese hamster ovary (CHO) cells. It is now widely used for a variety of mammalian cell types. Ham's F-12 may require serum or protein supplementation, depending on the type of cells being cultured. Ham’s F-12, is used for the culture of chondrocytes and rat prostate epithelial cells, Chick embryo pigmented retina, embryonic lung cells, and skeletal muscle.