Jacobus - Maid-O-Mist # 4 - 1/8" Angle Radiator Steam Vent, Jacobus - Maid-O-Mist "Jacobus - Maid-O-Mist Model # 4 - For radiators in room in which thermostat is located; A885 or where radiators affect operation of thermostat. Self-adjusting thermostatic control Float to prevent water escape, Reduces radiator noise Cut fuel consumption, Assures even heat distribution Lower operating costs, Improved nickel plated brass body, valve seat, solid float and bi-metal thermostatic element"