The WEGO4D-SYS Dual Channel Wide Band AFR Tuning Aid, from Daytona Sensors, is an air /fuel ratio metering system that accurately delivers air-fuel ratio readings for high-performance tuning applications, resulting in more efficient engine operation. The WEGO4D-SYS includes a built-in data logging that with the Dual Channel Wide-Band Exhaust Gas Oxygen Sensor Interface; two Bosch LSU4.2 five-wire, wide-band oxygen sensors; two 18 mm x 1.5 mm weld nuts for mounting the sensors on the exhaust pipe; and CD-rom software. Works for all carbureted and fuel injected engines.