I find this style to be the most accurate:
But i agree with crxgsr, if its off by 1-2 PSI its not a big deal, as it will be evenly off by the same amount for each tire.
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2002 TiAg M3 6mt
deoranged, dechromed, led tails, ZHP knob, UUC SS v3, GROM, OEM 220M 19's, Michelin Supersports
2006 YZF-R6, bunch of go-fast stuff