This uniquely design diagonal 8' foot square boat umbrella, can be used on practically any boat or simply at the beach. Constructed of marine quality stainless steel and lightweight aluminum, this umbrella will give you years of use. Hydra Shade is designed for use with any cylinder or rod holder opening and offers tilt and telescoping height adjustment. It is made to stay in place and remain in the cylinder by expanding the umbrella base. There are endless custom applications in which a Hydra Shade can be adapted to your boating lifestyle. Additional tie-downs are NOT necessary with the Hydra Shade boat umbrella. You can use a Hydra Shade on a kayak, sailboat, sportfish convertible, center console, bass boat, lake boats, deck boat, powerboat, paddle boats, even a dingy. Then when you arrive at a beach or sand bar, switch to the beach spike, and you are all set with a telescoping beach umbrella. The outside diameter of the Hydra Shade shaft is 1.25" making it a universal fit for any cylinder or rod holder. Included with the XL-150 4 Pc Kit is the (square tilting/telescoping marine umbrella, the expansion rod base, a spiral beach spike, and a heavy-duty carrying case.