the use of the flash 2 is easy as. on the screen it says 98 tune 95 tune and factory. it says to turn on and off the ignition in a step by step process. the use of the ajustments is also easy, rev limit, auto gearbox pressure, global spark, spark from 0 to 2k, 2k to 4k, 4k to 8k , wot fuel richer or leaner in a percentage, thermo fan controls hi and low set by degrees, f, speedo ajustments, boost ajustments diff ratio, . and much more if you have the skills to have them unlocked.