1-1/2 Thru Hull Connection C 

"Available in plain or chrome plated bronze, these fittings have a hose barb connection and are recommended for use above the waterline only. The flange is machined to fit the hull tightly and grooved to retain bedding compound. Minimum hull thickness 3/8"."

Hose: 1-1/2", Flange: 3-1/8", Max Hull Thickness: 1-7/8"

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