1,High Capacity Battery Pack BP28 2,Capacity:4400mAh 3,Output Voltage:3 ... Weight:128g 5,2*18650 Rechargeable Li-io Model: High Capacity Battery Pack FEREI | BP28Specifications of BP28:Size: 87.2mm* ... to 4.2VFeatures of BP28:* Professional lithium battery power pack , used for Bicycle Lamp B3/B5/B9 or Headlamp ... 2x18650 Li-ion battery inserted with protection circuit board. High Capacity Battery Pack BP28