Abstract: A telescopic jib of a load-handling device, having telescopically extensible sections in the form of fluid cylinders. An annular sealing assembly is employed at the end portions of the sections, in the form of a sleeve which defines an annular space with the end face of the fluid cylinder of greater diameter and the side surface of the fluid cylinder of smaller diameter. A floating ring is mounted in the annular space and has seals which engage the external periphery of said smaller-diameter fluid cylinder and the end faces of the floating ring. Annular grooves are coaxial in the external peripheral surface at the end of each said fluid cylinder and in the end face of the respective one of said sleeves such that, a support ring is accommodated in each pair of annular grooves. A rope-and-sheave system having at least two runs symmetrically extending with respect of the longitudinal axis of the jib is used to govern the motion of the sections.