Abstract: An improved stapler having a pair of stapler arms pivotally secured in confronting relation with one another, a first of the arms containing a plurality of staples and structured to dispense one of the staples towards the other arm upon being pivotally moved towards the other arm and meeting resistance. An opener segment is further provided and extends along a length of one of the arms, the opener segment including a proximal end and a distal end, with the proximal end secured to the arm. A blade is disposed between the opener segment the arm to which it is secured, at generally the proximal end of the opener segment which tapers towards its distal end so that the distal end can be introduced into a fold defined by a closure flap of an envelope until the envelope engages the blade and is cut thereby to open it.