hi colin : I have made about 6 of the plug in version for freinds and family , and getting good at making them , one thing that I forgot to mention was in hulda clarks book ,she mentions that using the zapper daily for one week will get candida numbers to almost zero It is impossilble to totaly kill cadida but through her research she she found the you can keep candida numbers very low using her zapper ,i combine this with olive leaf and it is very effective , I f you would like me to to build you one just let me know , the only part that is difficult to find is a 12 volt transformer that they used to sell intown I may have to get online to find that one , you will need this to transform the 110 volts household current to 12 volt dc current to allow the zapper to work correctly the rest of the parts i can get at radio shack