of this heavy duty unit are available:
WF- 1: Has two outlets that switch OFF when flow fails,
one for a heater and the other for a solenoid valve.
WF-3: Has four outlets—two for heaters, one for a
solenoid valve, and one to sound an alarm. Made for
WF-6: Has seven outlets that switch OFF when flow fails,
six for a Soxhlet extraction set-up, and one for a solenoid