HuntHawk 3.7V 350mAh 25C Lipo Battery(4PCS) with 4 In 1 X4 Battery Charger for Hubsan X4 H107C H107D H107L F180 F180C M61X, M62R, Udi U816 U816A&iexcl;&cent;JD385 U816A 3200 V939 V202 YD717YD716 Charging 4 battery at one time, Over charge protection, Short circuit protection Compatible With: Hubsan X4 H107C H107D H107L F180 F180C M61X, M62R, Udi U816 U816AJD385 U816A 3200 V939 V202 YD717YD716 Size of Each Battery: 37*20*7.5mm Package Included: 1* 4 in 1 Charger, 4* 350mAh batteries Chargering batteries on the same time to enable your rc helicopter to have enough replaced battery so that to have longer flying time.