Split grain leather is a layered cut of leather from within the lower levels of the top grain area of the hide. It is usually a lower layer of the hide, above the flesh. Also, below the full grain and the best top grain cuts. Though, it still provides a useful leather material.
The natural surface of split grain leather is not as dense, tight, and useful as full grain and top grain. Thus, it is often used in finishes of leathers that are colored, embossed, and the surface altered in some significant way. This allows it to offer some of the helpful qualities of a leather material, while having a visually pleasing and often-functional surface beneficial for leather products.