This is a 48V, 17A controller. These types of controllers are commonly (though not exclusively) used for E-bikes, electric scooters and mobility scooters. Most commonly known as the primary controller unit for an array of mobility scooters, like the Gio (Giovanni) MS3 Mobility Scooter or similar variations. Under Voltage Protection: 42V±0.5V. Case Dimensions: 105mm x 70mm x 35mm. Functions: Speed Limitation, Reverse.