The Oracle Ohm Meter can be used to test all your 510 connection atomizers and cartomizers. This is a great item to have when you are using rebuildable atomizers. Know exactly how many ohms your atty is so you can safely match your battery to the coil you have built. Features: -An on off switch -Red digital display -510 Ego style threaded connector -USB cable for charging -Replaceable battery (battery NOT included)