Base is set permanently into concrete. Sleeve provides vertical stability for the umbrella pole. Two pivot arms automatically lock the sleeve to the base upon insertion of the umbrella pole. The assembly is tamper-free. The sleeve will not separate from the base until the pole is removed. Thru holes are provided for a restraint bolt. Fastened with a nut and lock washer, the bolt secures the pole to the assembly while preventing the collar from sliding upward, exposing the pivot arms. Sleeve may be removed from the base when not in use by removing the bolt, sliding the collar up, and disengaging the pivot arms. A plug fits into the base when the sleeve is removed.