- USB connector (Digikey ED2989-ND) - USB A male to USB A male cable (Digikey 1175-1035-ND) - some 2mm pitch headers and attachments (standard Arduino fare, and you want a set of 2 per fan) - long enough strips of wire to reach the ends of your cage - heat shrink or tape - an iPhone charger - some permanent protoboard - a small LED - a resistor for the LED (I used a 1.2k to keep it dim) - a potentiometer (I used what I randomly had on hand)