Durable Material: Made of high-density, weather-resistant rubber, this umbrella wedge is stable during installation and won't easily slip. It features a pre-cut seam on one side for a better fit on the umbrella pole and works perfectly in the hole in the patio table. Easy to install and ideal for outdoor use. Perfect Fit: Suitable for umbrella poles up to 38mm in diameter, it fits snugly to the umbrella shaft, ensuring it doesn't slip and is stable and secure. Reusable and suitable for outdoor use. Please note that measurements are taken manually, so a slight error of one millimeter is possible. Easy to Install: The umbrella wedge can be easily installed in seconds and removed. Simply remove the umbrella and pole from the hole in the patio table. Install the umbrella wedge onto the umbrella pole. Insert the umbrella and pole into the hole in the patio table. Turn and gently push the conical wedge downwards to insert it snugly into the hole. Exclusive Design: The arc-shaped, conical design secures the umbrella in the correct position, preventing slipping and falling, ensuring safety and stability, and eliminating rattling. Wide Range of Applications: The wedge is suitable for umbrellas and parasols, large or small, to help them stand upright and prevent them from tilting and shaking in windy weather.