Digital Flex Fuel Wideband Failsafe Gauge W/ FF SENSOR. Incl. Bosch 4.2LSU sensor, AEM Flex Fuel Sensor, Black/Silver Bezels, Black/White AFR Faceplates, Black/White Boost Faceplates, Black Vacuum Faceplate & Black Lambda Faceplate Flex Fuel Wideband Failsafe Gauge, Monitor AFR, ethanol content and boost or vacuum, programmable engine protection, internal data logger, incl 4.2LSU sensor and Flex Fuel Sensor