This is one of the largest snails found in the tidepools. Generally they are in deeper water, but they often are washed into the tidepools by storms and large surf. The shells can measure up to 10” in diameter. The shells are amazing. When the snail is alive the shell may be covered in algae and smaller snails. Some will look like they have a “roof top” garden. When the snail retreats into its shell it will close its operculum. This is a hard cover with ridges. It protects the snail from drying out, as well as from predators. These snails can live for up to hundred years!