An electromechanical surgical system includes a hand-held surgical instrument; an end effector; and a shaft assembly for selectively interconnecting the end effector and the surgical device. The shaft assembly includes a transmission housing; an outer tubular body; a distal neck housing for interconnecting a rotatable drive member of the surgical instrument and a rotation receiving member supported in the end effector, wherein the distal neck housing includes at least one gear system configured to convert a rotational input of the rotatable drive member into at least two output forces to the end effector; and an articulating neck assembly interconnecting the tubular body and the distal neck housing. The articulating neck assembly enables off-axis articulation of the distal neck assembly, and wherein the rotatable drive member extends through the articulating neck assembly.