Features: Power is more intuitive, more beautiful Static no current, no power consumption Wider Use range:1-5 string lithium battery pack, 3-15 string of nickel-metal hydride batteries both can be used Specifications: Voltage:3.3-4.2V Wide application fields:lithium battery Using Method:connect display board positive and negative port with tested battery positive and negative port,digital tube will display real-time battery electricity quantity Display Electricity Quantity Parameter: 1.When battery voltage is over N*3.3V,it will illuminate 1 block electricity quantity (note:N represents battery quantity) 2.When battery voltage is over N*3.5V,it will illuminate 2 blocks electricity quantity 3.When battery voltage is over N*3.7V,it will illuminate 3 blocks electricity quantity 4.When battery voltage is over N*3.9V,it will illuminate 4 blocks electricity quantity 5.When battery voltage is less than N*3.3V,4 blocks display will be off;it represents battery is less than 3.3V,and you can charge the battery Product size:about 4.1*2*0.7cm/1.65*0.79*0.28inch Quantity:1Pc Note: Size for manual measurement, there may be a 0 to 2 for cm error, belongs to the normal phenomenon. And due to the difference between different monitors, the picture may not reflect the actual color of the item. Thank you! Package include: 1Pc X module