Designed for the CentriPro 4” three-wire single-phase sub motor.Manufacturer: CentriProModel: CB10412HP: 1 HPFEATURES Voltage Relays for installer convenience 115 and 230 volt models 208 volt relay available for low voltage applications Start Capacitors with resistors NEMA 3R enclosure for indoor or outdoor mounting Quick disconnect cover design will retrofit with other Q-D control boxes Multiple knockouts Two grounding lugs This 1 HP, 230-Volt control box is designed for us with 4 in. submersible well pumps fitted with 3-wire submersible motors of the same HP and voltage. George recommends control boxes! Well pump control boxes are used with 3-wire well pumps , prolong the life of the pump and for ease of maintenance. These are typically mounted on a wall above ground away from the well. The benefit of using a pump control box is that if any component takes a poopoo, then you can easily access them without removing the pump from the well. This can lead to easier & cheaper maintenance and prolong the life of the pump.