In this video we learn how to use an electric tester to test wires. You will first need to purchase a voltage tester that runs on double a batteries. When you press it the end will turn green and you are ready to use it. Test it out by pushing it into a plug you know works and see if it turns red and starts to beep. If you own a home or are renovating this can help you out a lot if you don't have switches around. You can place the tester on a wire to find out if it's on and then become safer than if you didn't have it.