X-Series Inline Wideband UEGO AFR Controller were fastest responding wideband air/fuel ratio controllers in an independent test vs. 17 competitors wideband AFR controllers; Patented X-Digital technology (Patent 9,575,030); Includes Bosch 4.9LSU wideband UEGO sensor; Factory calibrated resistor does not require free-air calibration, but technology allows for free-air calibration as sensor ages if user desires; Compatible with vehicle/system voltages up to 16V; 0-5V & RS232 output for data logging and feedback control, AEMnet (CANbus) for data logging and daisy-chaining multiple controllers up to 16 cylinders; Weather-resistant, low profile design;