Rule 13
Primary source
Verbatim text below is from the Electronic Code of Federal Regulations (eCFR), a public-domain U.S. government work. Always verify the current version with the eCFR before relying on it for any legal matter.
Full Text
Degrees of uniformity shall be expressed in terms of percentages. The percentages shall govern the portion of a lot which must meet the specifications of the grade. (These percentages shall not affect limitations established by other rules.) The minor portion must be closely related, but may be of a different group, quality, and color from the major portion.
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