We are a drug free alternative for pain management a tens unit has been around for over 30 years to help relieve pain. The nice thing about MY mini MASSAGERS/TENS unit that they are portable and small enough that YOU CAB RUN the lead wires through a blouse or shirt and place the unit in your pocket. The units RUN on a USB or wall charge and YOU CAN place the timer on whatever setting YOU want whether its 10 or 60 minutes. Another note is the tens unit has 6 different modes. 10 levels of strength that YOU control AS well.