Model SP154DPDT is a flow switch for use with the 9001and 9001EXP alarms. Switch will activate at 2.4 gallons (9 L) per minute of flow. AC, 125/250 volts, 5 amps, double pole, double throw. 1-1/4" NPT inlet and outlet. Class 1, Division 1, Group B, C, D. UL Listed.