# 350# Double Wall — Packaging specification equivalence: neck finishes, corrugated grades and pallet standards

For 350# Double Wall, specification type is corrugated_board; description is 350 pound Mullen burst test, double wall corrugated; primary dimension is 350 lbs/sq.in. burst; secondary dimension is Fibre Box Handbook: 120 lbs max weight per box; equivalence or compatibility note is UPS maximum weight per box: 100 lbs, recorded from its source on 2026-08-12.

- **Specification ID:** 350# Double Wall _(verified: appears in the quote below)_
- **Specification type:** corrugated_board _(our reading, not quoted from the source)_
- **Description:** 350 pound Mullen burst test, double wall corrugated
- **Primary dimension:** 350 lbs/sq.in. burst
- **Secondary dimension:** Fibre Box Handbook: 120 lbs max weight per box
- **Equivalence or compatibility note:** UPS maximum weight per box: 100 lbs
- **Additional data:** UPS: 100 lbs

## What the source says

> 350# Double Wall | 120 lbs | 100 lbs

## Sources disagree

More than one authority states this, and they do not state the same
thing. Both are reproduced with the source each came from.

### Description

uline.com says description is **350 pound Mullen burst test, double wall corrugated**, as of 2026-08-12.

> 350# Double Wall | 120 lbs | 100 lbs

Source: https://www.uline.com/Product/Detail/S-18339/Corrugated-Boxes-32-ECT/12-x-9-x-6-Lightweight-32-ECT-Corrugated-Boxes

uline.com says description is **350 lb. Mullen burst test, double wall corrugated**, as of 2026-08-12.

> 350# Double Wall | 120 lbs | 100 lbs |

Source: https://www.uline.com/Product/Detail/S-4406/Corrugated-Boxes-200-Test/12-x-9-x-6-Corrugated-Boxes


### Secondary dimension

uline.com says secondary dimension is **Fibre Box Handbook: 120 lbs max weight per box**, as of 2026-08-12.

> 350# Double Wall | 120 lbs | 100 lbs

Source: https://www.uline.com/Product/Detail/S-18339/Corrugated-Boxes-32-ECT/12-x-9-x-6-Lightweight-32-ECT-Corrugated-Boxes

uline.com says secondary dimension is **120 lbs**, as of 2026-08-12.

> 350# Double Wall | 120 lbs | 100 lbs |

Source: https://www.uline.com/Product/Detail/S-4406/Corrugated-Boxes-200-Test/12-x-9-x-6-Corrugated-Boxes


### Equivalence or compatibility note

uline.com says equivalence or compatibility note is **UPS maximum weight per box: 100 lbs**, as of 2026-08-12.

> 350# Double Wall | 120 lbs | 100 lbs

Source: https://www.uline.com/Product/Detail/S-18339/Corrugated-Boxes-32-ECT/12-x-9-x-6-Lightweight-32-ECT-Corrugated-Boxes

uline.com says equivalence or compatibility note is **350# Mullen equivalent row, double wall**, as of 2026-08-12.

> 350# Double Wall | 120 lbs | 100 lbs |

Source: https://www.uline.com/Product/Detail/S-4406/Corrugated-Boxes-200-Test/12-x-9-x-6-Corrugated-Boxes


## Source

- https://www.uline.com/Product/Detail/S-18339/Corrugated-Boxes-32-ECT/12-x-9-x-6-Lightweight-32-ECT-Corrugated-Boxes
- https://www.uline.com/Product/Detail/S-4406/Corrugated-Boxes-200-Test/12-x-9-x-6-Corrugated-Boxes

Last verified: 2026-08-12. Review by: 2028-08-11.
Part of [Packaging specification equivalence: neck finishes, corrugated grades and pallet standards](https://referencesource.org/packaging-material-specification-equivalence/).