Ride Control Systems Hadley Ride Control Systems are the choice of vehicle manufacturers and fleets because of their proven performance. Click on the images above to learn more about the specific product offerings. SmartValve™ Electronic height control systems have traditionally required several separate components: the valve manifold itself, an external sensor, and the associated electronics. That is, until Hadley’s SmartValve. Click to learn more. Air Horns Hadley knows a few things about air horns, mainly because Harold Hadley invented one of the first freon-powered, dual-trumpet horns in 1945, and some of the first electric and air powered horns ever created. In fact, air horns are commonly referred to as “Hadley Horns”. ) Ride Control Systems The choice of vehicle manufacturers and fleets because of their proven performance. Whether it’s our series of classic valves, our Next Generation height control valves, or our Smart Air Management Systems (SAMS™), you will enjoy significant benefits. Have a general comment or question? Drop us a message and someone on our team will reply within 48 hours (except weekends). Visit our support contact page to submit a US or European Support request.