The Nissan GT-R 370Z 350Z R-MAF Sensor offers nearly 220% more range vs. the factory MAF sensor(s).
The R-MAF Sensor help in high power application's where the factory MAF sensors are peaked out near 5V.  This will both cause a check engine light and also not allow the vehicle's computer to register any more incoming airflow which will cause the computer to not know the proper amount of fuel and timing to command to the engine.  
The Nissan GT-R, Nissan 370Z, Nissan 350Z HR and Infiniti G37 require two sensors.  The Nissan 350Z DE and Infiniti G35 require one sensor.
NOTE: Tuning is required with the R-MAF meters. R-MAF calibration files are included, along with fuel multiplier recommendations for your tuner to use. Because these sensors are repeatable within OEM specifications, the tuning is no more difficult than scaling the factory MAF meters to a larger (ie. 2 ¾ or 3”) intake. All intakes are built differently, and the exact placement (depth) of a MAF sensor, especially when a bend is present in the intake tube within several inches of the MAF sensor, effects MAF sensors voltage output, and can notably effect a MAF sensors reading. A quality GT-R/370Z/350Z tuner should be accustomed to tuning the factory GT-R/370Z/350Z MAF’s for these type of variances.