Spektrum Firma 85A Brushless Smart ESC / 4000Kv Sensorless Motor Combo. Spektrum Firma 85A Smart ESC for surface vehicles is waterproof and delivers power. Without additional sensors or modules, they feed battery and. ESC telemetry data straight to your radio in real time, all over one connection. Now includes a compatible 4000Kv Firma Brushless Sensorless. […]