Abstract: A hand-held unit for applying identifying microdots mixed within an adhesive base fluid, comprises a housing which mounts a container for the mixture and a canister of propellant gas. When an outlet valve of the canister is depressed, propellant gas flows from the canister into a nozzle whereby mixture is drawn from the container for discharge through that nozzle for application of the mixture to an article, a vehicle for example, for identification purposes.