I regularly interchange 5/16 and 8mm,,,, 1/2 and 13mm, and 3/4 and 19mm. They are all close enough for government work.

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95 SL500 Smoke Silver, Parchment 64K
07 E350 4matic Station Wagon White 34K
02 E320 4Matic Silver/grey 80K
05 F150 Silver 44K