Abstract: A telescopic post includes a tube set, a power unit, a rotation unit, a threaded tube unit and a threaded rod unit. The tube set includes internal tube inserted in an intermediate tube inserted in an external tube. The power unit is supported on the internal tube. The rotation unit is inserted in the internal tube. The rotation unit is connected to the power unit so that the power unit drives the rotation unit. The threaded tube unit is connected to the rotation unit so that the rotation unit rotates the threaded tube unit. The threaded tube unit is connected to the internal tube so that the threaded tube unit translates the internal tube. The threaded rod unit is connected to the threaded tube unit and the intermediate tube so that the threaded tube unit rotates the threaded rod unit and the threaded rod unit translates the intermediate tube.

Abstract: A self-driving telescopic post includes a cap, a brake, a directional bearing and an axle. The cap includes comprising a central aperture in communication with a chamber. The brake is inserted in the chamber. The directional bearing is inserted in the cap and engaged with the brake. The axle is inserted in the central aperture and supported by the directional bearing. The axle is allowed to rotate in a first sense of direction relative to the directional bearing so that the brake does not interfere with the rotation of the axle in the first sense of direction via the directional bearing. The axle is prevented from rotation in a second sense of direction relative to the directional bearing so that the brake interferes with the rotation of the axle in the second sense of direction via the directional bearing.

Abstract: A holder includes a plate, a bracket, a connector, an angle-retaining element, a fastener and a carrier. The plate is connected to an external object. The bracket includes two lugs extending from a positioning portion. The positioning portion is rotationally connected to the plate. The first lug extends from the positioning portion and includes a smaller aperture in communication with a larger aperture. The second lug extends from the positioning portion and includes a countersink hole. The connector includes an axle extending along a vertical axis from the bearing. The bearing is located between the lugs and formed with a tapered bore along a horizontal axis. The angle-retaining element includes an enlarged head inserted in the larger aperture and a tapered portion inserted in the tapered bore. The fastener includes is inserted in the angle-retaining element, the lugs and the bearing. The carrier includes a bearing for receiving the axle.