# Crash-lock bottom

> A crash-lock bottom is a pre-glued carton base designed to form as the flattened carton body is opened.

Canonical: https://dielinemaker.com/glossary/crash-lock
Last updated: 2026-10-26

Structures

## What it means in packaging

Also called an automatic bottom, it relies on linked bottom flaps and correctly positioned glue. It differs from a manually interlocking bottom. The label alone does not specify a load capacity or replace testing.

## A practical example

A packer opens the flat carton and its connected bottom flaps move into place, reducing separate base-folding steps.

## What to check

Verify the intended pre-gluing sequence, base seating and loaded sample with the converter.

## Use it in your project

- [Templates, dimensions and options](https://dielinemaker.com/learn/templates-and-dimensions)
- [Browse carton structures](https://dielinemaker.com/dielines)

## Related terms

- [Glue flap](https://dielinemaker.com/glossary/glue-flap) — A glue flap is an extra strip of a packaging blank that bonds to another panel to form a seam.
- [Tuck end](https://dielinemaker.com/glossary/tuck-end) — A tuck end is a carton closure whose main flap has a tongue that slides inside the carton body.
- [Packaging proof](https://dielinemaker.com/glossary/proof) — A packaging proof is a review version used to check a defined aspect of a design before production.

## Related

- [Packaging glossary](https://dielinemaker.com/glossary)