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 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