The swap that looks close
a larger mailer is the usual substitute for void fill beside the mailers, and it is the wrong one. Buying fill to plump a slack mailer fights the reason you chose a bag.
Packaging Suppliers lists Void fill separately because the jobs diverge as soon as the goods are on the bench.
What the right line actually does
Void fill belongs beside a carton, not inside a mailer that should have been a closer bag.
Loose fill and paper fill take a gap in a box. A mailer that is too big should be a smaller mailer.
If you have already mixed them
Pouring fill into a mailer splits the bag and still looks under-packed.
On Packaging Suppliers, orders that include Void fill and are placed by 3pm are dispatched the same day. UK delivery is free on orders over £50 ex VAT. Stocked items can be returned within 14 days.
Open Void fill when you already know this line. The sack or the pack is the unit on the page. Packaging Suppliers will still dispatch an order placed by 3pm on the same day.