On Sunday, February 2, 2020 at 5:32:21 PM UTC-5, wrote:
On Sun, 2 Feb 2020 12:31:09 -0800 (PST), trader_4
wrote:

IDK how you easily get rolls of tape into an envelope and have the
envelope be of uniform thickness.

I have mailed some weird **** in a padded envelope and had it get
there and by a like token I get stuff here I am not sure how they let
through. I will know in a few days.
I am really trying to stay with the flat rate boxes. That seems to be
the most "legal" and a good return on the recipient's investment.

First class package is a lot less, if it's under 16 ounces, that's the
way to ship it. It's almost as fast as priority, sometimes just as
fast, depending on where it goes. Even priority
mail using your own box and going by weight is usually less than the
flat rate PM boxes, unless it's a heavy item.
Priority mail is often very little more than regular parcel service,
depending on distance, etc.