A fastener application device comprising an hydraulically-operated tool head held by an operator and having an actuator trigger, a base structure having an air-operated power cylinder operatively attached to an hydraulic cylinder to supply hydraulic pressure to the tool head in response to operation of the actuator trigger. The tool head and base structure are connected only by air and oil lines that are long enough to allow the base structure to be supported on, for example, a workbench, requiring the tool operator to support only the weight of the tool head during a fastener installation sequence.