Specifications:1.It has Variable Voltage,range from 3.5V~4.1V; 2.It is a rebuildable ego battery,the Switch connector is rebuildable and the battery isrebuildable,also the battery and theatomizer could be taken apart.3.With LED light Blue,Green,Yellow,Red LED light to show the status of the voltage.4.Can match with CE5 rebuildable clearomizer 5.High capacity:750Mah 6.Switch protection and Atomizer protctionOperating parameters:1.quiescentelectroniccurrent:<10uA2.constantoutputvoltage:3.5v.3.7v.3.9v4.1v3.currentflow:≤1.3A(currentaccordingtodifferentconstantpressure,heatingwireresistance3ohm)Instruction:1.Smokingwhenthebatteryvoltageisbelow3.4V: ThewhiteLEDwillflicker10timestoremindtocharge.Duringcharging,itisnosmokingandstopworking2.Short-circuitprotection: Whentheoutputload(heatingwire)shortlycircuit,thewhiteLEDwillflicker3timesandbeonprotectionandalarmingcondition..3.Whenpuffmorethan10seconds,theconstantvoltageLEDindicatorwillgraduallyeliminate,youcankeepsmoking.