Fe Myers HJ100D Deep Well Jet Pumps, 1 HP, Cast Iron Durable machined heavy-duty construction pump body provides long product life Precision molded impellers and diffuser provide smooth, balanced performance and efficiency High quality proven pressure switch with adjustable on/off pressure settings. 20 PSI differential. Heavy-duty motor with double ball bearing design and voltage selection device Mechanical shaft seal with ceramic face and stainless steel construction for long seal life