The attractive, compact CuZn Bath Ball provides a quick, convenient way to fill your bathtub with clean, chlorine free filtered water. Bath Ball attaches easily and quickly to bathtub faucets. Inside the sphere is the same time-proven Power Disk used in CuZn's popular Shower Filter. To install just hang the Bath Ball from your tub's faucet. With typical water quality and family-use conditions, the Bath Ball will last about a year.