A wide range of compatible applicationsSimple operation at a glance, one key single on / off backlight / sleepIntelligent detection promptABS flame retardant environmental protection material, high temperature Master it at any time and anywhere, light weight / small size / built-in lithium battery / portable beltIt integrates a variety of powerful functions and functions precision LCD industrial appearance, simple operation, backlight function and long energy storageHTN wide viewing angle LCD green backlight capacity and easy charging37v/1000mah standby lithium battery type-C charging interfaceA wide range of compatible applicationsMeasuring 18650 lithium batteryVoltage and internal of AA / AAA alkaline batteryAnd displayed by LCDSize: 156 x 63 x 36mmCalibration :After dismantling the back panel, remove the marked ones first.Gently push up from the front LCD position, and then reversely remove the red wire on the back, so that it can be removedThen find a way to add a standard voltage of 5V between V+ V-.Press the button again to turn on the product to see if the voltage can be displayed normallyThen just remove the batteryShort-circuit the two points on this side, then plug in the battery, and the meter will automatically calibrate.After the calibration is successful, you can install it back as normal.Colour: blackMaterial: plasticPackage Contents:1 x digital display tester (Due to different batches, the appearance of the product may be different, but the function is the same)Only the above package content, other products are not included.Note: Light and different displays may cause the color of the item in the picture a little different from the real thing. The measurement allowed error is +/- 1-3cm.