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 four corner tie-down securing points and the quick release round rail mount make adjustment a breeze while creating an extremely secure shaded cockpit area. The umbrella's square shape measures 6ft. (1.8m) across the bow with a 5Ft (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.