This high-performance 40A Brushless ESC (Electronic Speed Controller) is designed to deliver smooth and precise throttle response for brushless motors in RC airplanes, helicopters, quadcopters, and multirotors. Compatible with 2S to 4S LiPo battery packs, it features an integrated 5V/3A Battery Eliminator Circuit (BEC) to reliably power your flight controller, receiver, and servo motors without needing a separate battery source.