This system will allow you to control the electronic engines RPM, either a set engine speed or a variable engine speed (Increase or Decrease). This system takes the radio remote signals or the manual switch signals (Positive or Negative) and converts them to allow them to control the engines RPM. The EDR I body measures 4"X4"X2". The body and connector are both weather proof, allowing versatility when you are installing the system. This product is very reliable and comes with a limited Lifetime Manufacturers Warranty.