Features:This product adopts full electronic closed loop design.It can control a wide range of engines.Fast and precise response to instantaneous changes.It can prevent reverse battery voltage, instantaneous pulse voltage.Easy to install, pre-adjustable, adjustable speed work idle.High reliability and it can withstand all kinds of electromagnetic interference around the engine.Specification:Model: ESD5500E Speed range: 1KHz ~ 7.5KHzThermostability: Max.+1%IDLE adjustment: 160±20Hz ~ 95% of rated speedDROOP adjustment: The minimum position is 15Hz +6Hz/ load current change per ampereThe maximum position is 400Hz +75Hz/ load current change per ampereExternal speed adjustment:±200Hz (external 1KQ)Weight: Approx.600g/ 21.2ozPackage List:1 * Engine Speed ControllerNote:Please allow slight error due to manual measurement. Thanks for your understanding.