Need a Separate Entry for Packaging Weight

[apegamer]

There needs to be somewhere that I can enter packaging weight separate from product weight.

Here's just one example of the problem: a poster weighs 2-3 ounces, but the box I need to put it in weighs almost a pound. I don't want to make the product weight 1+ pound because then when they order 2 posters it will bump the weight to over 2 pounds, when I'll just toss both posters into the same box. Not a huge deal domestically, but internationally each pound is a huge deal when shipping USPS.