The present invention relates to an instrument for manual operation (1) comprising a stem (2), an attendant member (3) disposed at a distal end of the stem (2), and a hand grip (4) disposed at a proximal end of the stem (2), having a substantially round shape and being fixed in the extended direction of the stem (2), wherein the stem (2) is placed eccentrically in relation to the hand grip (4), such that the body of the hand grip (4) has an axis that runs next to the axis of the body of the stem (2), at a side away from the attendant member (3), wherein at the functional side of the attendant member (3), the hand grip (4) possesses a first curve (5) and at the side opposite the functional side of the attendant member possesses a second curve (6) that differs from the first curve.