The wide and sturdy clamp attaches anywhere you want (from 0 to 6 cm) and can be attached to bleachers, benches, tailgates, boats, poles, fences, etc. If you are looking to replace a heavy and bulky umbrella stand, this is the perfect choice. Quick and easy installation. Ideal for umbrellas, flags, and fishing rods. The hole diameter can be adjusted by tightening the screw. The maximum thickness of the clamp is 6 cm. Please measure the thickness of the object to be attached before purchasing. Designed to provide instant and convenient shade. Ideal for covering barbecues, sporting events, outdoor activities, and other recreation. 3.8 cm diameter tube with thumbscrew for secure umbrella hold and height adjustment. Umbrella not included. IMPORTANT: Please check the diameter of your umbrella and the diameter of your deck or railing before ordering. Only fits poles up to 1.5" in diameter and deck railings less than 2.3" thick.