Abstract: A device for mutual locking concentrically, overlapping telescopic tubes which is actuated and maintained by axial pressure. The mutual locking device may be used to provide telescopic handles for floor brushes, brooms, mops and the like. An internal tubular section with a pin mounted to the end thereof is concentrically inserted within an external tubular section. A wedge-shaped tongue projects axially from the pin. Positioned circumferentially around the pin is an expansion bush provided with a wedge-shaped slot extending at least partially along the length of the bush and ending at a proximal end with asymmetrical entrance shoulders. Upon sliding the internal tubular section into the external tubular section, the tongue causes the bush to expand to lock the two tubular sections together by friction.