Measure before you open the range
Choose the mailer that fits the goods. A much larger bag folds and looks like a different pack.
Grey mailing bags are the opaque outer for soft goods. The page for Mailing bags is where Packaging Suppliers shows that line.
The published limit, if there is one
They are also called shoe bags. The category says they are European made from recycled film and 100% recyclable, and opaque so the contents are not visible.
A padded envelope is the lined bag. A grey mailer does not add that cushion.
Write the size down
Reorder grey, and the size.
A Friday order on Packaging Suppliers that includes Mailing bags aims for Monday. A bank holiday on Friday or Monday moves that delivery. The 3pm cutoff is still the same-day dispatch rule.
Open Mailing bags when you already know this line. Packs are the unit. Read how many bags are in the pack. Packaging Suppliers will still dispatch an order placed by 3pm on the same day.