Verhoeff kit is used primarily for staining elastin. However, it may be used for staining muscle fibers, as well as collagen. Elastic fibers consist of elastin polymers and elastic microfibrils that make up a 3D network in an extracellular matrix inside connective tissue (skin, elastic cartilage, vascular walls, lung tissue and in vocal cords). It can be used instead of the Weigert-Van Gieson kit. Visualization of elastic fibers is especially important in cases of emphysema (elastic tissue atrophy), arteriosclerosis (thinning and loss of elastic fibers), and many other cardiovascular diseases.