[All-round stress is more stable] Equipped with four knobs, so that the outdoor umbrella not have problems such as loosening of the space, sliding of the umbrella stand pole and tilting of the umbrella stand when the outdoor umbrella is fully stressed and fixed. Adjustable range: Φ1.12inch-1.57inch [Suitable for Three Scenarios] The bottom design is suitable for installation on concrete, wooden decks and lawns, and it comes with all required installation accessories. [Installation Use] The patio/dock umbrella base holder can also be used for flag pole mounts, light pole mounts, selfie camera mounts, shade sail pole mounts, and other types of poles suitable for residential and commercial use [WIDELY USED] This umbrella base stand is perfect for decks, piers, pontoons, patios, picnic tables, and any other place that can be secured with the included lag screws. [RUST-PROOF MATERIAL] This deck mount umbrella stand is made of heavy-duty metal base, which is . stainless. Colour:Black Material:Metal Package Contents: 1 * base bracket 1 set * screw accessories Only the above package content, other products are not included. Note: Light reflection and different displays may cause the color of the item in the picture a little different from the real thing. The measurement allowed error is +/- 1-3cm.