I have an appt. with my homeopath, who I have been seeing once a month for other things, she is going to use a machine on my arm, she did it for a couple of minutes on my last visit, and it went smoothly across my skin on my forearm, but, when she ran it on my upper arm it dragged along my skin, so it picked up the injury, she is giving me half an hours treatment with it tomorrow. I don't know what the machine is, but it not a Tens machine.