the power adaptor is an old ac dc power adaptor i had from a cd player. the fan is a 12 volt fan but fans over 4000 rpm work just fine running on 7 volts. yea, i thought about running a fan off a battery, but i had these two things and an idea, sometimes im just impulsive. the fan is still on the heatsink, i figure the air blowing out the sides and being disrupted by the heatsink fins would work well for circulating air and not just blowing directly on the cigars. and it made mounting it easyer. pb, the bag in the humidor is full of primeros. the bag on top of the cooler is a standard bag from cigar.com filled with humidy packs, thats what i use to humidify my humidor till i get my beads. it took some doing to get the humidity right, the bag half zipped seems to give off the right humidity.