Like many people who possess a TENs machines and will be looking at this listing already know, they are machines that are borrowed. One person buys one then its goes around a group of women a they all have babies. The only bit you don't reuse are the pads. These self adhesive pads stick well, can be removed and replaced several times (say for a bath, or to reposition)and do what there are meant to do. You only need one set per baby, and then they go in the bin. My wife used these with an Elle TENs machine and was happy with the effectiveness.