This part is a Starter Capacitor that fits many 230V Pump Motors. When diagnosing pumps for a no start condition where it is powered up but just hums you can hand spin start the motor by taking a screw driver to the shaft in the back and spinning it or you could touch the jet button and let the pump go to high speed and start then go back to low speed. If it runs on low speed then the capacitor could be bad. Please Note: Most of the time the Capacitor is not the cause it is the symptom so don't expect this to solve your pump issue long term. Most of the time it will run for a week or a month and quit again. You determine what capactior you need by the numbers stamped on it and the actual size of the capacitor. Capacitor Type Motor Start Motor Brand A.O.Smith/Regal Beloit, Century/Regal Beloit, Franklin Electric, General Electric Microfarad Rating 53-64 mfd Motor Parts Type Capacitor, Start Length 2-3/4" Part Dimensions 1-7/16"dia x 2-3/4"h Diameter/Width 1-7/16" Capacitor Microfarad Rating +/- 10% 53-64 mfd Electrical Connection 1/4" tab Voltage 230v