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Check your bimini frame hardware

Something that can be overlooked, would hate to have one snap during a trip.




2008 330EC
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Im sure i have some of both at the house
https://store.canvas-boat-cover-and-repair-advisor.com/Machine-Screw-Stainless-Steel-p/h1083.htm
Shoulder wont matter much as it will still be a tight enough fit and fit better than what was in there.
Amazon can fulfill all your needs
Google stainless 1/4 inch shoulder screw