Seat pedestal plugs. These plugs fit the 3/4” size pedestal holes only. They are a slight press fit, so they may require a flathead screwdriver to remove. The top cap is 1.5” in diameter.
IF YOU EXPERIENCE PLUGS BEING SLIGHTLY LOOSE DUE TO SEAT PEDESTAL HOLE BEING SLIGHTLY WORN. Add 1 to 2 wraps of electrical tape to bottom stem of seat plug and this will eliminate that issue.