An electric toothbrush, including a refill connectable to a handle via a coupling device. The handle has a drive mechanism, and the refill has a brush head and a motion transmitter functionally connected to the brush head for driving it. The handle has a coupling stem terminating with a free end and including a coupling pin extending from the stem. The refill includes a generally tubular portion formed by refill walls defining an interior space for accepting the coupling stem of the handle. The coupling device comprises a pair of mutually opposite and resiliently deformable cantilevered arms disposed adjacent to the refill walls in the interior space of the refill. Each of the cantilevered arms terminates with a coupling surface for engaging the stem's coupling pin for secure and disengageable connection between the handle and the refill.