A loading unit assembly includes a tool assembly having first and second jaw members and a pivot pin configured to pivotably couple the first and second jaw members. The first jaw member is movable with respect to the second jaw member between spaced and approximated positions, wherein the pivot pin includes a base portion and first and second stepped portions extending radially outward from the base portion. The first and second stepped portions are configured to pivotably engage the first and second jaw members, respectively.