These plugs come individually, or in a set of three plugs. These are for plugging up and protecting filter systems and machines with 1/4 inch hosing, and will fit most water ionizer models. The purpose of the plugs is to prevent water from leaking out of the water ionizer [or filter system] during transport.
It is important to save the plugs that come with your water ionizer. If you don't, then whenever you want to travel with your water ionizer or ship it somewhere you will take a risk of the water getting into the packing materials, box or even the electronics. This could harm the water ionizer.
White Plug: Will fit any 1/4" quick-connect fitting.
Red Plug: Will fit a 1/4" male barbed fitting.
Black Plug: Fits the port that the spout screws into.
Buy separately for $1.50 each or as a package of three for $2.50.