The Tens-3000 Advanced TENS Unit is a medicare approved TENS unit and system. So you know you are getting the very best in a 3 mode, dual channel TENS unit that utilizes microprocessor technology and safety features including a timer, cap and slide cover protection system.The Tens-3000 comes with everything that you need to get started. A comprehensive instruction booklet, the Tens-3000 Advanced TENS Unit, 2 lead wires, a battery and a secure, locking handsome carrying case. Now you are ready for hours and hours of pain relief and pain control. This unit boasts a dual channel three modes of operation including; burst normal and intermittent modes. This TENS-3000 can be worn all day and battery life is never an issue with the TENS-3000. Professionals truly prefer this device for many patients due to the simplicity of operation, reliability and versatility. There is adjustable pulse rate, pulse width and amplitude as well as the ability to select any of the three modes at anytime. This device the TENS-3000 is very easy to use and will last years and years with proper care.TENS devices work on the 'Gating' principle and therefore require the ability to produce adequate and therapeutic electronic signals which are transmitted to self sticking electrodes that adhere to the skin securely in order to provide adequate electrical stimulation which will block pain centers by providing a gentle relaxing therapeutic electrical signal that the brain interprets more easily than pain. This device also helps to improve the production of endorphins from your own body to the nerve endings that can further reduce pain signal. The use of the Tens-3000 Advanced TENS Unit can also help to exhaust pain sensing nerves so that even after the TENS has stopped there is some carryover of reduced or absent pain. You cannot go wrong with the TENS-3000 Advanced TENS System, complete with a timer, three mode use, dual channel with adjustable pulse rate, pulse width and amplitude as well as the safety features of a slide cover for the controls and a safety cap to prevent accidental intensity changes, all packed in a custom molded, locking carrying case. We hope you enjoy this product.