DOM Invincibat is constructed from Skinex, which is a virtually indestructible integral-skin polyurethane. It's safe for any age group, with any rubber, plastic, foam or cloth-covered ball. The 28" Invincibat is perfectly balanced, with a solid feeling 1" diameter grip and cushioned 2" barrel. The internal support of splinter-free fiberglass gives you that "real" feeling when hitting. Sold individually.