Set up this free-standing umbrella base on your patio or at any outdoor event without worry. The US Weight 80 Pound Free Standing Umbrella Base is crafted with a high-density polyethylene shell with UV protection that will not rust, dent, or fade, and can withstand the elements in any weather climate. This stable base must be filled with sand or gravel. Easily transport and setup the base with the removable wheel on bottom and hand grips for easier mobility. The 20.5″ diameter base features a 14″ high stem that accommodates poles from 1 ½” through 2″ thick. Inside the stem is a plastic post protector for the umbrella to rest on instead of a screw leaving the pole undamaged. The stem features two knobs made of polypropylene that tighten the umbrella securely in place for added stability and support. If used with a patio table, 14″ clearance is needed. All of the steel components are made of grade 304 stainless steel. Grade 304 stainless steel is also used in aerospace engineering and surgical instruments and will not rust. The umbrella bases come in two colors – black, bronze and white – and prefilled or empty options. High-quality free standing umbrella base with grade 304 stainless steel stem and hardware 20.5″ diameter resin base features a 14″ high stem accommodating poles from 1 1/2 “ through 2″ thick Post protector inside stem wont scratch or dent umbrella pole Easy transportation and setup with removable wheel on bottom and hand grips Empty base must be filled with sand or gravel for years of use in any weather condition. Do not fill with water.