[. . . ] Read these instructions attentively before the first use and retain them for later reference. [. . . ] Before every usage check the support to ensure that it is in a technically faultless condition!Slide the rod 2 out to the required height, until is sitting under the the rubber cushioning load to be supported. Release the locking lever 4 and ensure that the locking lever 4 engages into a groove on the rod 2 . Firmly retighten the securing screw 3 to secure the latching onto the rod 2 . [. . . ] With your other hand press and hold the locking lever 4 and slide the rod 2 back in. [. . . ]