Umbrella Holder for Stroller, Chair or Wheelchair Umbrella Holder: Material - High Strength Plastic, Length - 13 1/2 inches, Inside Diameter - 1 3/4 inch, Large 2 1/2 inch Thumb Screw, Light Weight 13.2 oz. Fits Golf and Travel size UV-Blocker umbrellas (umbrella not included) U-Bolt Mount: Color - Black Powder Coat, Material - Powder Coated Marine Grade Aluminum, Ball Size - 1 1/2 inch, Weight 5.6 oz. (2) U-Bolts, (1) 1 inch and (1) 1 1/2 inch with (2) nuts and (2) rubber end caps. Will fit any round tube 1/2 inch to 1 1/2 inch