The Mercury 4 - Day/Night Multi-Function Fan Speed controller puts the grower in complete control of their ventilation requirements. Plug your ventilation equipment into the Mercury 4, set the high/low fan idle speed, set the day night mode and your in business! Great for use with carbon filter ventilation systems. Temperature control range is 55°F to 95°F and includes a 6 foot temperature probe that is accurate to within 2°F. 6 Amps/120 Volts/60 Hz. 3 year warranty included.