Front Speed Controller for the Nanrobot D4 2.0 (New Generation) and D4 3.0 Scooters. 

Each sold separately.  To determine if you need this part or a different Scooter, check your wheels for  "RoadRunner Scooter" engraved on the wheels. If there is an engravement, order this Scooter.  Please contact RoadRunner Scooters for assistance.