I have been using the Prom 300 for 5 or 6 years now, tried other units, even more expensive ones, just weren’t like this one, couldn’t tolerate any other. Even a specialist had me try others, but just told me to stick with the Prom 300 since all the ones they had me try just didn’t work for me, most of them the intensity was too strong. I will keep ordering the Prom 300. Ordered electrodes from another company but they just didn’t fit in the wires, so I’ll keep ordering the wires from ESA medical too and the electrodes. Don’t know what I’d do without ESA , no problems with wires, electrodes or the Prom 300.