Y14.5M
5.10 Noncircular Features.
The fundamental principles of true position dimensioning and positional tolerancing for circular features, such as holes and bosses, apply to noncircular features, such as open end slots, tabs and elongated holes. For such features of size, a positional tolerance is used to locate the center plane established by parallel surfaces of the feature. the tolerance value represents a distance between two parallel planes. The diameter symbol is omitted from the feature control frame.

Example #2 would be correct.

(my interpretation from Y14.5M example)

Regards

Rick Stanich
CASA/MTA/MVA

IMC Magnetics
Tempe AZ
480.968.4441 x352

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