Dual-Size Pole Fit (1.5" & 1.35"): Securely holds 1.5-inch and 1.35-inch round umbrella poles using included reducer insert. Measure your pole diameter and deck hole size before purchase. Exclusive Single-Threaded Sleeve Compatibility: Fits ONLY Waterways & AquaStar single-threaded pool deck sleeves. Not compatible with multi-threaded sleeves, umbrella stands, or tables. Zero Tilt & Anti-Spin Lock: Upgraded stainless steel M8 thumb screw eliminates wobbling, spinning, or tilting—even in wind. 360° grip secures poles rigidly. Weatherproof PC+ABS Construction: UV-resistant polycarbonate + ABS composite. Withstands pool chemicals, heat (-20°C to 40°C), and resists fading/cracking. White finish. Tool-Free Installation: Insert into deck sleeve → Slide in umbrella pole → Hand-tighten thumb screw. No tools or technical skill needed.