Jackboxes are incredibly handy when you're trying to set up learning centers. This unit is versatile and easy to use. It has 4 positions with a 3.5mm input and individual volume controls. An additional 3.5mm jack is located in the center where an included 6' detachable patch cord with a 3.5mm plug connects to the audio source such as a computer, smartphone, tablet for mobile learning applications, or a multimedia player. Built with rugged ABS plastic housing for durability and safety, each jackbox has silver-plated contact points for a solid connection and moisture resistance, skid-resistant pads at each corner so they won't mar or scrape a surface. Grades Pre-K - 4.