Hillman 0.5625-in Black Polychloroprene Hole Plug in the Hole Plugs department at

The Hillman Group 58141 1-Inch Black Nylon Hole Plug, 6-Pack : Industrial & Scientific

Hardware Higginbotham Brothers

Hillman Black Nylon Hole Plug (Fits 7/16 Hole) : Industrial & Scientific

Hillman 2-Pack 0.3125-in Cork Stoppers in the Cork Stoppers department at

Hillman 2-Pack 0.75-in Rubber Grommet in the Grommets department at

Hillman 1-in Black Polychloroprene Hole Plug in the Hole Plugs department at

T-H Marine Brass Drain Plug with Rubber Plug - 5/8 inch Diameter - Pack of 2 Bait Well Plugs in the Boat Hardware department at

Hillman 3/4-in x 9/16-in x 1-in Rubber Stopper 881322

Hillman 2-Pack 0.875-in Black Plastic Hole Plug in the Hole Plugs department at

Hardware Higginbotham Brothers