The Cool Components PS-300 Power Supply is a variable voltage, universal, AC to DC power supply with selectable DC voltage. Versatile enough for any cooling or ventilation situation, this power supply provides manual speed control for all Cool Components products. With speeds selectable from 3 to 12 V DC, this unit can deliver the power to operate cooling products at any capacity. By simply adjusting the voltage, the PS-300 is capable of quietly cooling products when components are within close proximity of sitting areas or more aggressively when components are tucked away in cabinetry and closets. In addition, this unit plugs into a standard US 110/120V AC receptacle.