Takes a little while to get accustomed to the controls. I also have the knee sleeve, glove and ear clips. The instructions are a little vague of the main unit and to the accessories I have mentioned they are non existent. Tried YouTube but didn't get much joy there. If you have the knee sleeve on with 1 wire going to the clip and the other going to the pad attached to your leg you ready don't want to rest or touch your hand on the sleeve whilst it on as it gives you a fairly good jolt up your hand and arm well you soon learn not to after a few time. The unit itself is alright not flagship material but it's okay. Overall it does it's job tens wise still trying the EMS side of things but the results so far are mediocre was expecting a lot more after reading the initial writing and raves in the advertising. Had cheaper EMS machines that where just EMS and had better results. As a 3in1 machine at present I am only finding it so so, but maybe my opinion might be a little higher later as maybe I'm missing something in the instructions but I don't think so.IMHO it's a little better than some of the so called budget machines that are out there. Customer service is helpful