1、BATTERY TESTER: Lithium battery digital display monitor, which can measure battery voltage and internal resistance, with a wide measurement range. 2、SIMPLE CHARGING: The battery tester is small and portable, has built in 3.7V 1000mAh rechargeable backup lithium battery, with Type C charging interface. 3、LCD DISPLAY: With HTN wide viewing angle LCD display screen, the operation is simple and clear at a glance, and has intelligent detection prompts. 4、APPLICABLE BATTERY: This tester can be used to measure the voltage and internal resistance of 18650 lithium battery and AA or AAA alkaline battery. 5、MULTIPLE USAGES: Used for battery production line test, warehouse battery sampling inspection, photovoltaic inverter, battery maintenance, DIY electronics.