Convenient to use: the battery voltage tester has a switch function button, you can press to check the cattery capacity or real-time voltage and turn it off, with a design of alarm, battery meter display flashes when battery capacity is below 20 percent Easy to read: Designed with a clear LCD digital display, battery gauge indicator comes with a PVC waterproof screen protector with bright backlight, which allows you to read the results from different angles, low working power consumption, and the maximum is 5mA For different batteries: the battery capacity indicator is compatible with 12V/ 24V/ 36V/ 48V/ 60V/ 72V/ 84V lead acid battery, ternary lithium battery, polymer lithium ion battery, lithium ion battery 3-15 series, storage battery, water battery and more; Please note that they cannot be applied to lithium iron phosphate batteries, 1-2 Li batteries in series and more than 15 Li batteries in series Working voltage input: this package comes with 1 battery tester part with alarm, convenient to use and replace in daily life, the working voltage input ranges from DC 12V to 84V, which can automatically detect the accurate voltage according to the battery Voltage Widely applicable: the battery capacity voltage indicator can be placed in different places, such as garden, home, office, etc., reliable and can be applied for a long time, meeting your different needs, making life more convenient Number of shipments: 2 pieces (without battery)