A surgical device is described herein that can be used to fire different types and sizes of disposable loading units. In a preferred embodiment, the device applies parallel rows of surgical fasteners to body tissue and concomitantly forms an incision between the rows of staples during an endoscopic or laparoscopic surgical procedure. The device can be utilized with disposable loading units configured to apply linear rows of staples measuring from about 15 mm in length to about 60 mm in length and can be used to fire disposable loading units containing surgical clips and individual staples. A lockout mechanism is provided to disable the disposable loading units after firing.