Brand new innovative solution for sit on top kayaks, this unique pair of plugs avoids water flowing up through the drain holes but allows water to drain out. Made from long lasting silicon valve and grey in colour. Size: Medium hole 33 mm – 37 mm (1.3 inch to 1.46 inch). Other sizes available: Small hole size 29 mm – 33 mm (1.14 inch to 1.3 inch). Medium hole size 33 mm – 37 mm (1.3 inch to 1.46 inch) Large hole size 37 mm – 44 mm (1.46 inch to 1.73 inch) Extra-large hole size 44 mm – 48 mm (1.73 inch to 1.89 inch)