A dispensing canister-add-on-component assembly, comprising a dispensingcanister comprising a substantially cylindrical container having a closed endand an open end, said open end of the container being equipped by means of aferrule with a dispensing means； a substantially cylindrical add-on component；said component being positioned adjacent to the closed end of the container toform a generally cylindrical canister-component sub-assembly having aninterface between the canister and add-on component.
