A mech, or mechanical, mod is just a battery in a tube or a box. There isn't an electronic chip to change the voltage or wattage, or handle a display. A mech also provides none of the 'safeties' that a regulated (or reg) mod does such as polarity protection, atomizer short protection, and some other things. Another aspect of mechs is that they don't put out more than the battery has in it, and only what the battery has in it. A mech mod is basically a flashlight, the light being nicotine..