ishareflowers said: it will easily hold 500 seed packs with seeds/bulbs.
Can confirm. I shipped 500 dibs to DnD for last year's swap in the flat rate bubble mailer, and it contained a lot of big stuff like garlic cloves, walking onions, beans and a ton of squash packets. It was an effort, but it did fit. Those envelopes can hold a ton because you can force and stress them a bit since they are quite robust.
