Secondary drain pan shut-off switch. Safe-T-Switch Model SSW. detects clogged A/C condensate drains and shuts off system to prevent water damage. Safe-T-Switch®, 97092, Sensor, Multipurpose, Series: Safe-T-Switch SSW, 24 VAC/VDC, 5 (NC)/1 (NO) A, For Use With: Floor or Secondary Drain Pans