Abstract: A fastening tool includes an actuation device configured to actuate a drive engine of the tool to initiate a drive stroke. The actuation device includes a contact trip assembly operatively connected to the movable portion of the nose assembly. The contact trip assembly a lower contact arm connected to the movable portion of the nose assembly biased in the retracted position and movable to the extended position with the moveable portion of the nose assembly, and an upper contact arm operatively connected to the lower contact arm. The actuation device includes a trigger assembly that includes a trigger, a trigger arm pivotally supported by the trigger and configured to interact with the upper contact arm, and a check pawl configured to engage an opening in the upper contact arm when the upper contact arm moves downward to prevent the tool from being operated in a contact trip mode.