An open electrosurgical forceps for sealing tissue includes a pair of first and second shaft members each having a jaw member disposed at a distal end thereof. The jaw members are movable from a first position in spaced relation relative to one another to a subsequent position wherein the jaw members cooperate to grasp tissue therebetween. Each of the jaw members includes an electrically conductive sealing plate for communicating electrosurgical energy through tissue held therebetween. At least one of the jaw members includes a knife channel defined along a length thereof which is dimensioned to reciprocate a cutting mechanism therealong for cutting tissue disposed between jaw members. An actuator having a rack and pinion system advances the cutting mechanism from a first position wherein the cutting mechanism is disposed proximal to tissue held between the jaw members to at least one subsequent position wherein the cutting mechanism is disposed distal to tissue held between the jaw members.