Location of lot numbers?

[Blue Petes]

I am in the process of buying some federal heavyweight 20 ga loads and would like to know where the lot number is located on the box. Also if you know any lot #'s for the 3 inch #7 you could provide me with so I can compare them to the ones on the boxes to insure I am looking at the right number I would be very thankful. Last are there any bad/good lots for those shells that y'all have tested? Thank you again