This product is suitable for various kinds of RC batteries, such as LiPo/Li-ion/Li-ion/Li-battery Fe. When the voltage drops below the preset value, there will be a buzzer with a red LED, the preset value is 3.3V. Press the key that can change the voltage setting and save. Features:Sharp LCD display, used in low-light conditionsCompact and highly portableSuitable for various kinds of RC batteries, such as LiPo/Li-ion/Li-ion/Li-battery FeEasy to installSpecification:Weight: 14gDimension: 44*32*14mmDisplay: LED displayVoltage sensing accuracy: 0.01Vutterance gauge of unit range: 0.5-4.5VAtotal voltage gauge: 0.6-36Vought of voltage in 1S test mode: 3.7-30VAlow voltage larm mode for: 2-8SValue range Alarm Set: OFF-2.7-3.8V Package Includes: 1pcs/2pcs x Lipo Battery Voltage Tester