L404F PressureTrol Controllers provide operating control with automatic limit protection for pressure systems of up to 2070 kPa, or 300 psi. These controllers may be used with steam, air, or noncombustible gases, or fluids noncorrosive to the pressure sensing element. L404T,V PressureTrol Controllers are for use on oil burner systems for pressures up to 1035 kPa or 150 psi. L404T features high pressure limits and breaks a circuit on oil pressure rise above setpoint. L404V is for low pressure limits and makes a circuit on oil pressure rise above setpoint.