Usage Tips:APPLICABLE BATTERY: Supports: 1. 3-20 series lithium battery pack, 2. 4-24 series lithium-iron battery pack, 3. lead-acid battery of 12V, 24V, 36V, 48V, 60V, 72V, 84V. This product also supports custom mode in range of 9.5-100V.DISPLAY: The product uses digital display LCD with backlight, equipped with a strengthened waterproof screen, it displays both battery voltage and remain capacity simultaneously, enable users to view the state of battery clearly.POWER-OFF MEMORY: After cutting off the power supply of the voltmeter, the function setting keep the state before power-off.LOW VOLTAGE ALARM: The low voltage alarm work when battery power is less than 10% (battery flash). This reminds you that the battery needs to be .LOW POWER CONSUMPTION: The voltmeter has a very low power rate, at normal mode, its self-current consumption is below 15mA, while low-power-consumption working mode is below 1mA.CALIBRATION: A calibration screw hole allows to adjust the voltmeter to zero bias by simply twisting the screw for enhanced precision and convenience.EASY TO INSTALL: The voltage meter can be mount on panel or installation easily with nut and bracket included in the package.WATERPROOF & DUSTPROOF: The voltage meter features a waterproof level of IP67, which means it can resist water splash in most situation.Colour:BlackMaterial:plasticPackage Contents:1 x battery capacity testerOnly the above package content, other products are not included.Note: Light reflection 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.