Feature: Portable、easily to test atomizers anytime、anywhere. This tester can show you the ohm easily by screwing on an atomizer. It can test out the bad atomizers by testing the resistence. It will read a 1 in the first digit to the left if there is no current flow through the device. Accurate to +-0.4%. Will read from 0.01 to 9.99 ohms. It can test all ego/510 thread atomizers. Its test amperage is only 3 milliamps and will not produce heat at the coil of the tested atomizer.Use the method is simple:1. Twist the atomizer or the battery into the corresponding Screw thread.2. Turn on the tester switch.3. Display will immediately show the resistance value and voltage value.Package contain:1 x tester