Rumbrella's Windproof Umbrella design is fortified with nine resin-reinforced fibreglass ribs and a vented double canopy. This helps it flex slightly to ensure it withstands powerful gusts without turning inside out.And the Rumbrella® Windproof umbrella features a double-vented, wind-defying structure that makes it ideal for use in strong winds. It's just what we need during these summer storms.