The 6-1/2” extension between the rubber and the wingnut on these plugs allows a seal to be made farther inside a pipe. They are commonly used for skimmers, cleaner lines, and therapy heads, or can be used to bypass a leaking section of plumbing near the wall of the pool to test the remainder of the line. The plugs are made with durable brass hardware, solid rubber, and a corrosion-free wingnut. Our heavy-duty plastic wingnuts are about the same strength as brass wingnuts (except in particularly dry environments), but are lighter and will not corrode over time. Anderson Plugs are built with durability in mind and will remain easy to tighten and leak-free even after years of use.