---
type: guide
title: "Custom Cardboard Mailers Explained for Ecommerce Brands"
description: "How custom cardboard mailers work: inside sizing, E flute against B flute board strength, kraft versus white top printing, recycled options and real order minimums."
resource: https://www.4over4.com/guide/custom-cardboard-mailers-explained
tags: ["guide"]
generated:
  by: "process:4over4-mapp-build"
  at: 2026-09-08T01:19:44.025Z
timestamp: 2026-09-08T01:19:44.025Z
sources:
  - resource: https://www.4over4.com/guide/custom-cardboard-mailers-explained
    title: "Custom Cardboard Mailers Explained for Ecommerce Brands"
status: stable
---

# Custom Cardboard Mailers Explained for Ecommerce Brands

How custom cardboard mailers work: inside sizing, E flute against B flute board strength, kraft versus white top printing, recycled options and real order minimums.

See [all guide concepts](index.md).

- Page type: guide
- URL: https://www.4over4.com/guide/custom-cardboard-mailers-explained