This is the E-flite 50-Amp Pro Switch-Mode BEC Brushless ESC V2. This ESC is high-quality, efficient, sensorless and has an integrated Switch-Mode BEC. It is capable of up to 50 amps continuous current when using 2- to 3-series Li-Po battery packs. You can drive up to 7 analog or 6 digital standard-sized servos with the BEC on any recommended input voltage. It has advanced programmable features such as low voltage cutoff, braking, timing and throttle input range.