<p>The ball-joint (2) has a mounting (1) for a spherical socket (4) with an opening (5) at right-angles to the piston rod (3) passes through a slit (19) in a surround piece (26) and passes through an opening (18) in the spherical socket. The piston rod has a threaded end (16) screwed into a threaded blind bore (15) in the ball. The ball has a cutout (17) in the side facing the opening in the spherical socket.</p>
