What is the spider’s body covered with?

The body of spiders, like most arthropods, has a hard protective shell that is formed from the material chitin. This shell is often referred to as an exoskeleton. The only exceptions are the part of the belly, which consists of a soft leathery material.
Since chitin cannot stretch when the animal grows loose, spiders are forced to shed it as it grows, and a new one grows in the place of the old one, but larger. During their entire life, on average, they change the coating from five to ten times.