An end effector for use with an adapter for a surgical instrument. The end effector includes first and second jaws that are pivotally coupled to each other and are movable between open and closed positions by a dynamic clamping assembly that is selectively movable between a starting position and an ending position relative to the first and second jaws. A first positive jaw opening feature is provided on the first jaw and a second positive jaw opening feature is provided on the second jaw. The first and second positive jaw opening features are configured for contact by the dynamic clamping assembly as the dynamic clamping assembly is moved in an opening direction to apply opening motions to the first and second jaws. The first and second positive jaw opening features may be longitudinally offset from each other.
