Q – Can you please explain the meaning of the following tolerance symbol? Which type of standard is this, ASME or ISO?

Edward C.


Hi Ed,

The profile tolerance does not adhere to either the current ISO or ASME Y14.5 standards. Neither standard permits the word “BILATERAL” in the feature control frame. Also, both standards require that the geometric symbol be placed in the first compartment and the tolerance value in the second compartment, followed by the datum references in the third, fourth, and fifth compartments, if applicable.

Thanks for question,