A description is given of a filling system for the metered delivery of a lubricant, comprising a container for receiving the lubricant, wherein a rod interacts with the container, is mounted movably with respect to it and forces the lubricant out of an outlet opening arranged in the container. The invention also relates to cartridges for use in the filling system. One of the underlying objects of the invention was that of providing a filling system which can be supplemented by simple workshop means and enables the operator to fill up a lubricating system in a vehicle effortlessly within a short time. This object is achieved by a filling system in which the rod is rotatably mounted with respect to the container and turning of the rod in a predetermined direction of rotation brings about a reduction in the storage volume in the container or a handheld device and in which the rod has means for establishing a rotationally fixed connection with an adaptable turning tool.