The Pelican Medium Scupper Plugs are a set of four units designed for sit-on top kayaks with scupper holes measuring 1.5-1.75 inches. These plugs are made by Pelican, a well-known brand in the water sports industry. They are manufactured in China and do not come with a California Prop 65 Warning. The plugs are an accessory that helps prevent water from entering the kayak through the scupper holes.