ELECTRIC TOOL POWERED BY A PLURALITY OF BATTERY PACKS AND ADAPTER THEREFOR

An electric power tool includes a main body supporting a tool. An electric motor is housed in the main body and configured to drive the tool. A plurality of battery interfaces is integrally formed on the main body, each battery interface having a positive battery terminal and a negative battery terminal. Each battery interface is configured to removably receive a positive battery terminal and a negative battery terminal of a corresponding one of a plurality of battery packs and to electrically connect the plurality of attached battery packs in series with the electric motor. Each of the plurality of battery packs comprises a movable latch configured to engage a corresponding engagement structure defined on or near the corresponding battery interface.