A tube length has to clear the roll. A square box crushes it or fills the corners. This page stays with white postal boxes.
Packaging Boxes keeps White postal boxes apart from a brown cube. The category describes white postal boxes that qualify as a Royal Mail small parcel, in 125WK/T, some of them shell-and-slide with foam. The outside maximum still applies.
What this collects
White postal boxes are the white finish for a parcel that is meant to look like post, not like a warehouse carton.
The notes below stay on white postal boxes. A brown single wall carton can be the same size and the wrong finish.
Before the order goes in
Stay inside the small parcel maximum the changes page gives as 450 x 350 x 160 mm on the outside. White does not raise that limit.
On Packaging Boxes, orders that include White postal boxes 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.