This Square Cockpit Umbrella is the next generation of the already popular Boat ● Umbrella from Magma. More than your ordinary umbrella, the Cockpit Umbrella has been manufactured for use in the harshest of marine environments. Made with non-corroding, fade resistant acrylic nylon materials, the windproof design will not allow the canopy to turn inside out or lose its shape in gusty wind conditions. The 100% UV block protective coating reduces the temperature under the canopy by 20 DegreeF, keeps you and your guests out of the harmful sun's rays while the four corner tie-down securing points and quick release round rail mount make adjustment a breeze in creating an extremely secure shaded cockpit area. The umbrella's square shape measures 6ft. (1.8m) across the bow with a 5 ft. (1.5m) fiberglass shaft assembly. The canopy is stretched over specially designed fiberglass bow ribs that will not rust or stain the fabric while the main shaft is constructed of flexible double-cored fiberglass for extra strength. The 7/8" or 1" (22mm or 25.5mm) round rail mount is made of 18-8 Stainless Steel and 356 Anodized Aluminum that adjusts to fit any angle on vertical stanchions or horizontal railings quickly detaches without tools leaving no hardware on the rail.