Welcome、Please read the instructions carefully.Features:Designed for 12V Lead-Acid battery SLA、 AGM、 GEL、 VRLA battery5 segments LED indicator、 10% capacity resolution.Build-in MCU chip、 accurate measure battery capacity.Very slim size.Reverse polarity protection.This gauge is designed for discharge and idle condition usage. It is not recommended for charging condition.(If you want to know the charged power、 please remove the charger and wait 3~5 minutes)Specifications:Material: ABSColor: BlackSize: 40 x 21 x 11 mmRating Input Voltage: DC12V/24VRating Input Current: £¼10mAPower-off leakage current: £¼0.5mASuitable battery type:12V Lead-Acid battery SLA、 AGM、 GEL、 VRLA battery. Package included:1 x Battery Indicator MeterWish you a happy shopping.