Product Details: Update your semi with enhanced brake control in demanding or slick operating conditions, with the Haldex PLC Select 1M Electronic Control Unit that ensures you're Ready for the Road Ahead™. Once the brakes are engaged, this replacement component determines when to release brake pressure to prevent lockup or sliding. Manufactured with an advanced microprocessor to identify optimal brake release times and repair needs. FleetPride is your First Click in Heavy Duty®.