This is an 11.1V 1500mAh 3S 40C LiPo with LED and EC3 connector from E-Flite. E-flite® Thrust VSI (Voltage Status Indicator) Series lithium polymer batteries feature an integrated voltage checker so you can check the status of your battery on the go. A series of LED lights will indicate the state of charge at the press of a button. Compact E-flite® Thrust Series lithium polymer batteries are rated at 40C to deliver excellent power and longevity without a major size or weight penalty. Each battery is equipped with popular EC3™ (EFLB50006S40 is equipped with an EC5) and JST-XH balance connectors compatible with a wide range of chargers (such as those from Dynamite and Orion®) and ESCs, and they're available in a variety of capacities and cell counts for use in park flyers up to large airplanes, helis and drones.