The Waterway 715-9870 barb plug is designed for compatible manifold and plumbing applications using a 3/8 inch slip size. A plug like this is useful where an unused branch or port needs to be closed off cleanly in order to match the intended system configuration.Small plugs are easy to overlook, but the correct Waterway part can make a major difference in preserving a tidy, serviceable plumbing layout. It is especially practical in manifold systems where some outlets may be intentionally left inactive.For compatible plumbing and manifold service, this Waterway plug is a practical solution for sealing an unused 3/8 inch slip opening. Waterway barb plug 3/8 inch slip size Helps close unused manifold or plumbing ports Useful for configurable branch layouts Supports cleaner and more controlled system setup