This cast iron umbrella stand is great for most patio umbrellas (standard pole 1.5 in.). With its sleek, modern style, it will be a great accompaniment to any setting. It features a patented Dual-Purpose Stem. You may use the full stem for free-standing shade, or remove the top section of the stand stem for under-the-table application. As this item is composed of iron, it is not uncommon to experience some rusting, especially in humid or coastal environments. Rusting is not considered a defect in this item and is not covered under the manufacturer"s warranty. Measurements: * Outside diameter of the neck (tube only) is 2 inches * Inside diameter of neck is 1.75 inches * Thickness of neck wall is 0.25 inches * Knobs measure up to 1.75 inches * Knob would measure 1.5 inches if screwed in flush to the neck wall * Durable cast iron * Several finish options * Standard pole size of 1.5-inch diameter * Dual-Purpose Stem * 2 tightening knobs * Commercial quality