Abstract: A telescopic shaft including a male member slidably fitted in the interior of a female member. The male and female members are rotatably locked by providing, on contact surfaces, a succession of small longitudinal ribs meshing with one another. One of the members includes at least one smooth longitudinal region devoid of ribs. The longitudinal region extends from one end of the one member to an intermediate point. The longitudinal region is engaged by a projection extending from the other member. The projection is directed towards the one member and acts as an abutment against the ends of the longitudinal region to limit the possibility of one member sliding with respect to the other member to prevent disassembly of the two members.