Push-pull prop

A push-pull prop comprising:

• an inner tube and an outer tube which are reversibly fixed to each other, wherein the inner tube is at least partially inserted into the outer tube,
• a threaded bar at least partially screwed into a threaded portion of a first end of the inner tube, said first end being opposite to a second end of the inner tube inserted into the outer tube,
• said inner tube, outer tube and threaded bar being arranged coaxially to one another along a common axis of the prop,
• a fixing head comprising a coupling portion fixed or fixable to a first end of the outer tube, said first end being opposite to a second end of the outer tube adapted to receive the inner tube, and a locking portion rotationally connected to said coupling portion, so that said outer tube is rotatable with respect to said locking portion about a rotation axis of the outer tube coinciding with the common axis of the prop in order to screw or unscrew said inner tube on or from said threaded bar,
• said locking portion of the prop being further configured to rotationally connect to a first connecting element of the prop at a first surface to be propped, so that the prop is rotatable about a first tilting axis of the prop perpendicular to the rotation axis of the outer tube;
• wherein said threaded bar is configured to rotationally connect to a second connecting element of the prop at a second surface to be propped, so that the prop is rotatable about a second tilting axis of the prop perpendicular to the rotation axis of the outer tube and parallel to the first tilting axis of the prop;
• wherein said fixing head comprises:
• an anti-friction sliding element shaped as a solid material ring, interposed between the coupling portion and the locking portion, and
• a retaining element of the anti-friction sliding element between the coupling portion and the locking portion,
• wherein said anti-friction sliding element is a bronze ring operating as a bushing and wherein said retaining element is a screw.