Abstract: The present invention relates to a balancing, positioning and fixating assembly for balancing a treatment device, comprising balance arm having a first arm end and a second arm end, a stepper part having a first part end and a second part end, the first arm end is connected with the second part end via a first pivot joint so that the balance arm is movable in relation to the stepper part, and an angulator device is arranged in connection with the second arm end, the angulator device is configured to connect the treatment device to the balance arm and to facilitate movement of the treatment device in different angles, wherein a spring device having a predetermined spring force is arranged along the balance arm, the spring device has a first spring end and a second spring end.

Abstract: A chain with mutually connected chain links (1, 2) each comprising a back portion and two parallel wall portions protruding substantially perpendicularly therefrom, in which wall portions corresponding rivet holes have been provided in each of the two and members of the chain link, wherein the chain links (1, 2) are connected with one another by means of an end member of a chain link with a comparatively narrow (2) back portion which is inserted into an end member of a neighbouring chain link with a comparatively broad back portion (1) such that the rivet holes (1c, 2c) in the parallel wall portions of the two end members (1a, 1b,2a-2b) are positioned opposite one another for engaging a river (3) or a shaft member.