Hyperion G3 Cx 0550 Mah 1s 3.7v 25c/45c Pack for Blade 120sr Heli Battery Pack Dimensions: 58.8 mm x 18.8 mm x 6.2 mm Battery Pack Weight 14.35 g/0.51 oz. Specs At A Glance: Battery Voltage: 3.7 V; Battery Capacity: 550 mah; Battery Dishcarge Wire Size: 20 awg; Battery Balance Connector: n/a ;Battery Discharge Wire Length: 15 mm Connector: JST Suggested Accessories: Hyperion EOS 0606i DC Charger, Hyperion EOS 0606i AC/DC Charger, Hyperion EOS 0615 Duo Charger, or Hyperion EOS 0720i AC/DC Charger, HP-UM6PADAPT (charge 6 U type packs at once using this parallel adapter plug)