GSD Projekt Zwei GmbH

Here are some specifications for potatoes:
Size
Potatoes are graded and sized before packing and shipping. Size A potatoes are typically 1.75–2.5 inches in diameter and weigh more than 10 ounces. Size B potatoes are typically 1.5–2.25 inches in diameter and weigh 5–10 ounces. Size C potatoes are typically less than 1.5 inches in diameter and weigh 5–10 ounces.
Variety
Russet potatoes and some types of sweet potatoes are size A potatoes. Larger white, red, and purple potatoes are size B potatoes. A small variety of white, red, purple, and fingerling potatoes are size C potatoes.
Freshness
Fresh potatoes should be free from signs of sprouting, injury, cuts, bruises, shrinkage, physiological disorder, insect damage, disease, and any type of discoloration. The color of fresh potato skin should be russet, pale yellow, or red, with netted or smooth eyes.
Other specifications
potatoes must be firm, fairly clean, fairly well-shaped, and free from freezing, blackheart, late blight, southern bacterial wilt, ring rot, soft rot, and wet breakdown.