UltrafireBlueXSL186502400mAh3.7vRechargeableBattery HighcapacityandreliablepowersourceUltrafire2400mAhbatteryNon-protectedcelldesignVoltage:3.7V(alsocalled3.6Vand4.2V)Capacity:2400mAhLength:2.52 Width:0.71 Weight:1.57ozLength:6.4cmWidth:1.7cmWeight:44.5gram