Feature: Accurate Measurement: The current measurement accuracy can reach 0.001A, accurately measuring battery voltage, current, power, capacity value and other information. Touch control: The screen can be locked to prevent accidental touch. Brightness Setting:[AUTO] (automatic brightness) When the backlight brightness of the battery meter is in automatic brightness mode, the battery meter automatically adjust the backlight brightness according to the ambient light.[] (Fixed Brightness) When the backlight brightness of the power meter is in the fixed brightness mode, the backlight brightness of the power meter remains constant and is not affected by ambient light. Bluetooth Settings: Bluetooth connection app for real-time viewing, user parameter APP operable settings.(This feature is only suitable for Android Bluetooth) Widely Used: Products such as RVs, bed bikes, electric vehicles, emergency power supplies, energy storage power supplies, measuring equipment, medical equipment, various instruments and meters that can be used for battery equipment. Basic parameters: Working voltage:8.0~120.0V Working Power dissipation (backlight off):3.4mA Working Power consumption (brightest backlight):25mA Sleep power consumption:0.3~0.7mA Power off:0.4~0.5mA Accurate voltage acquisition:1.0% Current acquisition accuracy:1.0% Accurate capacity acquisition:1.0% Capacity Detection Range:0.1~9999.0Ah 350A sampler current:0~500A Ambient temperature:-10~60 Color: As Shown Material: PVC + Plastic + Metal Package Contents: 1 set x TX21 Bluetooth coulomb meters Only 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.