RoadRunner 48V 25A Speed Controller for Sensorless Motors - E Revision is for brushless, sensorless motors only. Can work with sensored motors also, by leaving motor's hall effect cable unplugged. Can also be used for brushless Wilderness Energy hub motors but some connectors will likely have to be changed. The 25A controllers are the following dimensions: 4.2 inches X 1.7 inches X 6.25 inches (7.7 inches includes the mounting brackets). The 25A controllers weigh 1.65lbs.