A surgical instrument configured for coupling with a plurality of loading unit types, the surgical instrument comprising: a handle portion a body portion coupled to the handle portion a sensor tube movably disposed within the body portion, the sensor tube configured to engage a loading unit, wherein the sensor tube includes a contact supported thereon and a potentiometer disposed within the body portion and electrically and slidably coupled to the contact, wherein the potentiometer is configured to output a sensor signal corresponding to a predetermined distance traveled by the contact relative to the potentiometer upon engagement of the loading unit with the sensor tube.
