The X-Series Wideband UEGO AFR Sensor Controller Gauge (PN 30-0300) measures 2 1/16th-inch (52mm) in diameter, and features a modern, visually striking faceplate and new seven-segment center display that is 87% larger than the 30-4110 AEM Wideband Gauge’s center display. This creates the perception of a larger overall gauge, but in a common 52mm size Compatible with easy mounting. Its slim depth (less than one inch overall) and ultra slim cup depth of .200-inches dramatically increases its application base and potential mounting locations. X-Series Wideband UEGO AFR Controller Gauge were fastest responding wideband air/fuel ratio controllers in an independent test vs. 17 competitor wideband AFR controllers Includes Bosch 4.9LSU wideband UEGO sensor<br/> Factory calibrated resistor does not require free-air calibration, but technology allows Compatible with free-air calibration as sensor ages if user desires<br/> Compatible with vehicle/system voltages up to 16V<br/> 0-5V & RS232 output Compatible with data logging and feedback control, AEMnet (CANbus) Compatible with data logging and daisy-chaining multiple controllers up to 16 cylinders AEM’s 30-0306 X-Series -30in/Hg~35PSI / -1~2.5BAR Digital Boost Display gauge combines incredible looks, increased readability and a multitude of new, easy-to-use features! It is a must Compatible with users who want highly accurate boost pressure readouts up to 35 PSI or 2.5 BAR in their high performance vehicle. 2-1/16th (52mm) gauge diameter Compatible with easy mounting in gauge pods<br/> Slim 0.825” overall gauge depth and 0.200” cup depth – mount them virtually anywhere!<br/> Programmable center LED is 87% larger than original AEM gauges<br/> 24 green outer LEDs Compatible with quick reference to engine parameter<br/> User selectable standard or metric display ( -30in/Hg~35PSI / -1~2.5BAR)<br/> Peak/Recall via gauge face buttons<br/> User selectable threshold warnings