The Bendix® EC-60™ Standard Controller is a member of a family of electronic Antilock Braking System (ABS) devices designed to help improve the braking characteristics of air braked vehicles - including heavy - and medium-duty buses, trucks, and tractors. Bendix ABS uses wheel speed sensors, ABS modulator valves, and an ECU to control either four or six wheels of a vehicle. By monitoring individual wheel turning motion during braking, and adjusting or pulsing the brake pressure at each wheel, the EC‑60™ controller is able to optimize slip between the tire and the road surface. When excessive wheel slip, or wheel lock-up, is detected, the EC-60™ controller will activate the Pressure Modulator Valves to simulate a driver pumping the brakes. However, the EC-60™ controller is able to pump the brakes on individual wheels (or pairs of wheels), independently, and with greater speed and accuracy than a driver. Note: Cab-mounted EC-60™ controllers are not protected against moisture, and must be mounted in an environmentally protected area. Frame-mounted EC-60™ controllers may be mounted on the vehicle frame, but only in locations where they will not be subjected to direct tire spray.