Caretaker 5-Port Valve Base O-Ring Kit
These 2 o-rings go around the base unit and one goes inside the valve separating the base plate from the upper housing. One O-ring is placed between the bottom and center plate of the valve to make sure the 2 parts are sealed and helps prevent water from leaking. The other o-ring is placed inside the top housing.
These are great to use if you see a leak around the band clamp of the 5 port.