The Banana Boat Waterproof Speaker Case allows you to take your music on the go! Built with a rugged protective body that will keep your expensive phone or music device safe and dry while you still enjoy your favorite tunes even in the harshest of environments! The spacious body has room for most phones music players keys credit cards driver s license and cash! The use of a 1/8-inch headphone jack allows the case to be used universally with most phones and music devices with a headphone port. Simply install three AA batteries plug the speaker jack into the device s headphone port secure the device in the case with your other valuables close the latches and voila! Whether floating in a pool enjoying the rays at the beach hiking or even mountain climbing this speaker case provides the perfect barrier between the environment and your valuables. The waterproof speaker case uses a unique pressure system that equalizes internal and external air pressure.