It is not possible to say which is the best zapper , you need to match them to your needs, to start with i made one using Hulda Clark s instructions in her book that didnt seem to do anything, then I bought one from Healthleads UK - very good but very expensive - it eventually broke - I also bought a mini frequency generator from them - useful if you know what the bug is you are trying to kill but time consuming as you have to keep programming it. I now have a terminator - this is much smaller & the inbuilt copper discs mean you dont have to have leads attached to you which can get in the way & stop you doing other things while zapping. I use the terminator for long periods of constant zapping, use good quality batteries & it lasts ages, you can get slight burns though if you dont move it around frequently. This zapper has been the best so far. I also had a mains zapper but that was a not very good & you had to stay sitting by a plug & I didnt like being hooked up to mains electricity. These are just my experiences but I hope it gives you some help.Good luck.X