May I just also add to this that it is a serious safety hazard if you have children? I honestly think that it is a very dangerous device and any child keen and curious about it will definitely put a finger in it and get zapped! I tried it once as a drunken bet and it hurts like hell; didn't feel the electric shock but you would not want that with children in the house. The insect repelling spray or cream is a better alternative. You just have to get used to it and it won't bother other friendly insects!