Abstract: A compact telemanipulator arm assembly with a rotatable gripping tool is disclosed that is watertight and has a sleek profile suitable for penetrating into narrow underwater passages of nuclear reactors. The assembly has a plurality of elongated arm elements jointed together end-to-end in series relationship. Bending of adjacent elements is achieved by an axially aligned motor housed within one of the adjacent elements, a screw-nut system that converts the motor shaft rotation to axial movement of a slider, and mechanical linkage that converts the slider movement to relative pivoting of the elements. The gripping tool is mounted on a tool support on an end element. Tool gripping members are operated by a first axially aligned motor housed within the end element and a screw-nut system that converts the first motor shaft rotation to axial movement of a slider.