The largest type of seal is the elephant seal. Elephant seals are divided into two species: the Northern Elephant Seal and the Southern Elephant Seal. Adult males can reach lengths of up to 20 feet and weigh up to 4,500 pounds, making them the largest pinnipeds. These seals are named for their large size and the inflatable nose of the males, which resembles an elephant's trunk. They are known for their impressive diving capabilities and spend much of their lives in the ocean, only coming ashore for breeding and molting.