A stabilizser for tripods and the like. The stabilizer includes a rod for each tripod leg, arranged for connection on one side to the corresponding leg and converging, on the other side, in a common connection. The rods each comprise at least two rod members slideable telescopically one with respect to the other in an axial direction, and an arresting component for reversibly locking the rod members one with respect to the other according to the pre-selected adjustment, wherein the arresting component is of a unidirectional type, active in only one direction between the rod members for releasably blocking their relative axial sliding in one direction and for permitting free axial sliding in the opposite direction.