4 ordered a receipt broken. The feeling of "shock" Power is so light that some just feel their finger scratched and did not catch the joke. I had a high school student being and the effect was final, with immediate cry and release pen. In addition, by turning the tip pen really wrote while here there is not even mine. And it looks like it is metal pen on photos but in reality it is totally fine plastic ... It will not expect much joking with because its life is very short ... Also, battery is not standard, so this gadget is immediately subjected to an obvious planned obsolescence. In short, it is no more than the selling price. Whatever price for this there was a good pen that lasts several years. I do not recommend this gadget to buy.