The 1st Choice Plus Tens unit is the more sophisticated of our high quality, value-for-money TENS units. This compact easy-to-use unit can treat two pain areas at once. With the added benefit of "Pulse Width Adjustment". You can now control the depth and smoothness of the pulse to improve your comfort. Other features include Pulse Rate and Intensity adjustment as well as Burst, Continuous and Modulation (Massaging) modes. Everything you need from a TENS machine at a great price. Want more info? See 1st Choice Plus TENS Manual.