This simple, easy to use Ohm Meter allows you to measure the resistance of your atomizer safely before use on a mod. The digital readout displays ohm rating to the hundredth decimal. Just screw your addy in and read the number. Uses 2x AA batteries, not included. AA batteries not included Digital readout Simple on/off switch Displays ohm rating to the hundredth decimal Just screw your addy in and read the number