1. The product defaults to a ternary lithium battery L03 S voltage (L03) when powered on for the first time. 2. Measurement of ternary lithium battery (L): from L03 S to L12 S. 3. Measurement of iron lithium battery (F): from F03 S to F14 S. 4. Acid battery (P) measurement: P12V/P24V/36V/48V. 5. Custom mode: high and low voltage settings, set the voltage values for fully charged and fully discharged. Low voltage alarm function: When the battery level is equal to or lower than 10%, the red battery grid flashes. There is a power-off memory storage function. Voltage measurement range:DC 7-40V Working current:less than equal 20mA Display mode: LED screen Measurement of ternary lithium iron: 3S-12S Measurement of lithium iron batteries: 3S-14S Acid battery measurement: 12V/24V/36V/48V Button Description: 1. On the normal display page, short press the button to turn off and on the display. 2. On the normal display page, press and hold the button for 2 seconds to enter the settings page. Note: Please check as much as possible to make sure the item is what you need. Tips:The product may be updated constantly ,Due To Different Batches, The Actual Product May Have Slight Differences Or Color Differences, Which Does Not Affect Use. Specifications:C: red display Colour:As Shown Material:Plastic Package Contents: 2 x Capacity Voltage Meter