7 CFR § 51.2836 - Size classifications.

The size of onions may be specified in accordance with one of the following classifications.

Size designation	Minimum diameter		Maximum diameter
	Inches	Millimeters	Inches	Millimeters
Small	1	25.4	2 1/4	57.2
Repacker/Prepacker 1	1 3/4	44.5	3	76.2
Medium	2	50.8	3 1/4	82.6
Large or Jumbo	3	76.2	( 2)
Colossal	3 3/4	95.3	( 2)

1 In addition to the sizes specified, a lot of onions designated as Repacker or Prepacker shall contain at least 60 percent or more 2 inches or larger in diameter.

2 No requirement.