About 12 months ago, some time after a knee replacement, I decided to ressurect my 20 year old T.E.N.S. unit.I looked on the net for help, and chose to contact Physio Supplies, as they looked the most promising.As my tube lf electrode gell had shattered ( a problem with old age?) I asked them about obtaining a replacement supply. Their EMail came back VERY quickly, explaining that gell is out, sticky electrodes IN. I ordered a supply, which arrived very quickly, and have since re-ordered a couple of times. Their website is informative, and very easy to use- the best I've come across so far,their products reliable, and service and attirude are excellent.They have a very wide range of Physio supplies, at reasonable prices