1. Uninterruptible Power Supply (UPS) Module, 5a High-Current Spring Thimble Version, Supports Simultaneous Charging And Discharging, Provides Stable Voltage Output, Can Measure Parameters Such As Battery Voltage, Current, Power And Remaining Power Through 12c Interface Communication, And Detects The Module In Real Time Working Status2. Onboard Battery Protection Circuit, Preventing Overcharge, Over-Discharge, Over-Current, Short Circuit And Reverse Connection, Balanced Charging Electricity, Stable And Work3. There Are 4 18650 Batteries On Board, Which Can Maintain Standby For A Longer Time;4. On-Board Warning Indicator Light Makes It Easy To Check Whether The Battery Is Connected Reversely.5. Onboard 5v Voltage Regulator Chip Can Output 5a (Max) Current, Providing Sufficient Power For NanoOutput Voltage: 5VCharging Power Supply: 8.4V 2AControl Interface: 12CProduct Size: About 100 x 79mmBattery Specifications: 2600mAh, 18650 Batteries X 4 (Two In Parallel And Two In Series)Through Hole Diameter: About 2.5mmNote:Different Batches May Have Differences In Product Appearance, Color, And Printed Characters, Which Will Not Affect The UseColour:As ShownMaterial:Acrylic + plastic + metalPackage Contents:1 x UPS Power Module (B)1 x Transparent Acrylic Protection Board4 x 18650 Battery1 x 8.4v Power Supply1 Set x Screw Mounting AccessoriesOnly 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.