A battery holer is one or more compartments or chambers for holding a battery or batteries. In the case of dry cells the holder is also usually responsible for making electrical contact. In the case of wet cells cables normally make contact with posts or terminals like commonly found on automobiles or emergency lighting and power. Battery holders developed in parallel with batteries over time and as battery package sizes shrunk so did the holders. Today's battery holders typically are either a plastic case with the shape molded in the housing as a compartment that accepts batteries or a separate plastic holder that is mounted with screws, eyelets, glued or double sided taped down. Using either coiled spring wire or flat tabs that press against the battery are the two most common methods of making the electrical connection inside a holder. External connections on battery holders are usually made by contacts with the following feature: PC pins, Surface mount feet, solder lugs or wire leads.