Holley EFI now offers a fully standalone 2-1/16" Air/Fuel Wideband O2 Gauge Kit with 0-5 volt analog output allowing data logging capability. Our gauge kit includes a slim mounting analog face gauge with 5-foot weathertight sensor harness and 4-foot power/ground/lighting harness allowing for flexible mounting locations and a Bosch LSU 4.9 wideband O2 sensor. Designed specifically for use with all EFI systems and available in both black and white face versions.