Abstract: The arm includes a supporting member and a plurality of telescoping members located therein and having a subsequently decreasing diameter. The supporting member and the telescoping members are interconnected by means of at least one kinematic train which is formed by endlessly guided pulling members. These pulling members, preferably steel belts, interconnect three respective adjoining telescoping members. The belts are mounted to the respective outer two telescoping members and guided for return at the upper and bottom area of the center member. When displacing the telescoping member having the largest diameter relative to the supporting member any further telescoping member is displaced relative to its outer adjoining member by a corresponding distance. This design leads to a rigid smoothly operating telescoping arm having a small structural height.