Heavy-Duty Construction: Reinforced Edges & Stainless Steel Triangle-Rings Built to withstand wind speeds up to 39 mph, our custom shade sails are engineered for stability. We use extra-wide 4cm (approx. 57 inch) webbing-wider than standard market options-to reinforce the edges, preventing fraying and snapping. Each corner features a premium stainless steel Triangle-ring, tested to withstand 2000 Newtons of pulling force. Whether it's a sudden gust or constant tension, this sail is designed to hold strong.