This purchase includes the following: (1) brand new M4 Pressure switch MODEL # 9013FSG2J24M4 PRE-SET ON 40 OFF 60 GENUINE SQUARE D BRAND DESIGNED TO PROTECT YOUR PUMP SHOULD IT RUN OUT OF WATER Brand: Square D Pre-set ON 40psi OFF 60psi... Can be adjusted to 30/50 also or any combination between 40/60 and 30/50.... This switch has a LOW PRESSURE CUT OUT to protect your pump. This means you will have to manually restart the pump via the little lever on the side of this switch whenever the pressure at the switch falls 10PSI below the cut in pressure.