There are various different types of mods with the main three being either Variable Wattage, Variable Voltage or Mechanical Mods. Variable Wattage and Variable Voltage work in a very similar way with the chip inside the device regulating the power to the coil within the tank attached to the mod. Mechanical Mods do not have any chipset inside and are for use by a select group of vapers that know how to use these safely to get the best results out of their kits.