Features 1、True four‑wire 1Khz AC sinusoidal battery internal resistance meter. The maximum resolution of internal resistance is 0.00001Ω, and the maximum measurement range of internal resistance is 200.0Ω. 2、The maximum voltage resolution is 0.00001V, and tested lithium battery voltage can display to 0.0001V, ensuring high sensitivity. It can measure positive and negative voltages. 3、It can measure lead acid, lithium ion, lithium polymer, lithium iron phosphate, alkaline, dry battery, nickel metal hydride, nickel cadmium, button battery, etc. 4、Professional design and reasonable structure, easy to replace and install 5、Made of high quality ABS material, sturdy, durable and long service life. Specification Condition: 100% Brand New Item Type: Internal Resistance Tester Material: ABS Color: As shown in the picture Battery: Lithium battery Model: 18650 Battery Capacity: 2000 mah Internal Resistance Measurement Format of accuracy ±([Percentage of accuracy] [Least Significant Digit]) Range Resolution Accuracy 200mΩ 0.1mΩ 0.5%+5 2Ω 0.001Ω 0.5%+5 20Ω 0.01Ω 0.5%+5 200Ω 0.1Ω 0.6%+5 The above data is in the range of 5%-95% of the gear position. If it is not within this range (less than 5% gear range range, or greater than 95% gear range range), the error may be greater than the above accuracy. Voltage Measurement Range Resolution Accuracy ± (% reading +% range) 1V 0.00001V 0.15+0.015 10V 0.0001V 0.15+0.010 100V 0.001V 0.15+0.015 Positive and negative symmetric error±(0.012%+ 5 digits). Temperature drift within normal use temperature(10℃ to 40℃)is 100ppm/℃. Package List 1 x Internal Resistance Tester 1 x Clip 1 x Probe Test Line 4 x Pin 1 x Instruction Manual