Grading:
Since you’re mentioning that the product adheres to USDA and DFA grading standards for shelled walnuts, your product would likely fall into specific grade categories for walnuts, such as:
U.S. No. 1 (highest quality, including intact halves and large pieces)
U.S. No. 2 (includes more broken pieces, but still usable for food)
U.S. No. 3 (usually smaller, broken or defective pieces)
For international trade, it’s important to specify the exact quality or grade as per USDA standards when describing the product. For example, you could list the product as “USDA Grade A Shelled Walnuts (Halves and Large Pieces).”

Size Tolerance: 20% halves or greater (according to buyer’s specifications) with the balance being ¾
halves or large pieces. No more than 3% can be smaller than large pieces. 
Color: Light & Extra Light
Variety: The product is made up from mostly Chandler, Howard, and Tulare variety.. 
Shell Fragment: 1 per 500 lbs. or better. 1 per 200 lbs. for J spec or K spec. 
Metal or Glass: None allowed 
Packaging: 25 lb. net corrugated cardboard carton made of food grade material with plastic liner
inserted in case to preserve freshness. 
Certification: Certified Kosher by the Orthodox Rabbinical Council of San Francisco.  
Food Safety: Processed in accordance with GFSI regulations and SQF Level Two certification.  Microbiological testing is performed by an independent laboratory on samples taken at the time of packaging. 
Best Before Date: Up to 18 months from harvest date at optimum storage conditions of 32-38°F (0-3°C).  Up to 6 months when stored in ambient conditions (70°F or higher).