Clamp Fiberglass Umbrella for Beach Chairs UPF 100 Umbrella fastens to any tubular (square or round) frame piece on vertical level. Also the clamp allows to adjust the length of the shaft and 35 deg. Tilt from clamp level. 8 Fiberglass ribs of 4mm diameter and spreaders for more flexibility which will not kink or bend out of shape. Fiberglass ribs are better steel ribs. 4 foot Diameter canopy with UPF 100+ protection ; Umbrella weighs 1.1 lbs Heavy Duty Polyester Fabric with properties of silver coating for added sun protection and durability. Open Dimensions (inches): 48 Diameter with Steel Tubing shaft of 14 mm diameter. Folded Dimensions (included carry bag): 44 x 2.7 x 4