Fangrui Product Details After Replaced The Storage Battery, Release The Red Clip Of The Tool, If The Tool Is Still Beeps, It Means You Have Replaced The Battery Successfully, If No Voice, Indicating Fuse Burned. Using This Simple Tool When Replacing Your Car Battery Help You These Problems. The Power Management System With Core Processor Can Display Battery Voltage (to Prevent The Use Of Low-power Batteries, Which Cannot Achieve The Purpose Of Battery Without Power Failure); It Can Display Current (can Be Used For Leakage Detection, And Can Also Understand Whether The Car Is Static Current In The Startup State) Battery Clamp Anti-reverse Connection Protection (red Light Turn On To Remind You After Reverse Connection) Overcurrent Protection (with Built-in 5a Fuse); Instructions For Use If The Digital Tube Does Not Display After The Battery Is Clamped, Please Clamp The Battery Again If The Car Battery Is Seriously Depleted, Plugging In The Battery Tool Is Equivalent To Directly Charging The Car Battery, A