The entire board may be preheated to a temperature that all components can withstand indefinitely. Then localised heat is applied to the component to remove, with less heating required than from cold. Most frequently, a hot air (or hot gas) gun, with a nozzle of appropriate size and shape, is used to heat the component, with nearby components shielded from the heat if necessary, followed by removal with tweezers or a vacuum tool. Removal of multi-pin components with a soldering iron and solder removal tools is impractical, as the solder between the component and the pads remains in place, unlike solder which can be removed from a hole.