HE2000 ac and dc hydraulic power units are self-contained modular power systems that come in fully assembled or component form. The power units from Haldex Barnes Hydraulics, Rockford, Ill., can be built with a variety of standard and pressure-balanced pumps, motors, switches, mounting surfaces, and steel or plastic reservoirs. Bolt-on manifolds with integrated valves can be used with double-acting circuits. Each power unit controls up to four hydraulic cylinders. They handle pressures to 4,000 psi and flow rates from 0.50 to 7 gpm.