The accuracy for these gauges includes linearity, hysteresis, and repeatability. The three front buttons turn gauge on or off, zeros guage reading, and cycles through functions. The four memories are user-settable of 1,2,3,4 or four wheel designations of LF, RF, LR, and RR. The gauges come factory calibrated and is pass code protected. The shut-off is selectable from 1 minute to 8 hours, and comes factory defaulted to 5 minutes.