Fish maw is a good source of collagen, proteins, and nutrients. Collagen provides a wide variety of skin benefits, such as helping to improve skin tone, and tissue health. Furthermore, many Chinese people considered fish maw as a traditional delicacy that represents fortune and health.

(eatconnection.com)

Fish maw contains rich proteins and nutrients such as phosphor and calcium. It nourishes 'yin', replenishes the kidney, and boosts stamina. ... Furthermore, fish maw does not contain cholesterol and therefore it is a very valuable health-enhancing ingredient suitable for long time consumption. (emperorbrandbirdnest.com)

From the manufacturer: 

South America Peruvian Big Butterfly Fish Maw #392 (13-16 heads/lb)  Fish maw has a high therapeutic effect and is rich in protein, colloid, phosphorus, and calcium. It is regarded as a treasure for women. It has the ability to nourish all parts of the body, and it is a precious product that nourishes and moisturizes. Fish maw is sweet in taste and mild in nature, enters the kidney and liver meridian; It has the effects of nourishing the kidneys and jing essence [hormone balance, immunity, and longevity], nourishing muscles, hemostasis, removing blood stasis, and reducing swelling.