Handpieces which comprise characteristic data storage systems electronically storing characteristic data, devices comprising these handpieces, methods of characterizing the device components, and methods of adjusting the device components based on stored characteristic data are described. The handpieces can be repeatedly connected to, disconnected from, and reconnected to an optical energy system comprising at least one optical energy source and at least one controller by a treatment provider. When the handpieces are connected to an optical energy source and a controller, the component characteristic data is accessed and used to adjust one or more of the components in order for the components to function together within a pre-determined tolerance. Once the components are connected and adjusted, the device can be used to provide an optical energy based medical and/or cosmetic treatment to a tissue such as, for example, human skin.