A proportioner for dispensing plural component materials, said proportioner comprising: an electric motor; a first pump, said first pump being connected to a source of a first material and having an output which has a first pressure; a second pump, said second pump being connected to a source of a second material, which is different from said first material, and said second pump having an output which has a second pressure; and a controller; characterized in that: said first and second pumps are reciprocating piston pumps; said electric motor has first and second ends; the proportioner further comprises: a first gearbox connected to the first end of the electric motor; a first crankshaft connected to the first gearbox; a second gearbox connected to the second end of the electric motor; and a second crankshaft connected to the second gearbox; said first pump is attached to said first end of the electric motor by the first gearbox and the first crankshaft; said second pump is attached to said second end of the electric motor by the second gearbox and the second crankshaft, and said controller has provision for a user-selectable setpoint and is adapted to continually compare said first and second pressures and to regulate the higher of said pressures to said setpoint. an electric motor; a first pump, said first pump being connected to a source of a first material and having an output which has a first pressure; a second pump, said second pump being connected to a source of a second material, which is different from said first material, and said second pump having an output which has a second pressure; and a controller; characterized in that: said first and second pumps are reciprocating piston pumps; said electric motor has first and second ends; the proportioner further comprises: a first gearbox connected to the first end of the electric motor; a first crankshaft connected to the first gearbox; a second gearbox connected to the second end of the electric motor; and a second crankshaft connected to the second gearbox; said first pump is attached to said first end of the electric motor by the first gearbox and the first crankshaft; said second pump is attached to said second end of the electric motor by the second gearbox and the second crankshaft, and said first and second pumps are reciprocating piston pumps; said electric motor has first and second ends; the proportioner further comprises: a first gearbox connected to the first end of the electric motor; a first crankshaft connected to the first gearbox; a second gearbox connected to the second end of the electric motor; and a second crankshaft connected to the second gearbox; a first gearbox connected to the first end of the electric motor; a first crankshaft connected to the first gearbox; a second gearbox connected to the second end of the electric motor; and a second crankshaft connected to the second gearbox; said first pump is attached to said first end of the electric motor by the first gearbox and the first crankshaft; said second pump is attached to said second end of the electric motor by the second gearbox and the second crankshaft, and said controller has provision for a user-selectable setpoint and is adapted to continually compare said first and second pressures and to regulate the higher of said pressures to said setpoint.