Empty space in a container is the enemy of safe shipping. Every gap between pallets or cargo lets the load shift in transit — and a shifted load means damage, claims and, at worst, a dangerous container to open. Cordstrap D-Connect dunnage bags are inflatable bags that fill those voids and brace the load in place. Here's how they work and how to choose the right one.
What is a dunnage bag?
A dunnage bag is an inflatable air bag placed in the gaps between cargo to stop it moving. Compared with timber blocking and bracing, D-Connect bags are faster to deploy, more effective at preventing both lateral and longitudinal movement, and leave no waste timber behind. They're CTU compliant, AAR approved, and made from 100% recyclable polywoven material with high puncture and moisture resistance. Browse them in the Cordstrap range.
The five AAR levels — matching the bag to the job
Dunnage bags come in five performance levels set by the Association of American Railroads (AAR). In short:
- Levels 0–2: used inside containers to fill empty spaces between pieces of cargo — the most common everyday use.
- Levels 3–5: heavy-duty bags for securing particularly heavy cargo such as paper or steel coils.
Getting the level right matters: too light for the load and the bag can fail; heavier than needed and you're overspending. If your cargo is dense or heavy, tell us and we'll confirm the level.
Choosing the size
The right bag depends on the void size, the height of the cargo and your shipping setup. Popular sizes we stock:
- 900mm × 1200mm for smaller gaps between pallets.
- 900mm × 2100mm for standard container voids — also available boxed in bulk (100) for high-volume shippers.
As a rule, the bag should fill the void snugly when inflated — not so small it rattles, not so large it's overstretched.
Fast, easy inflation
D-Connect bags are built for speed on a busy loading dock. The valve sits on the edge of the bag facing the door, so it's easy to reach, and the D-Connect inflator fills a standard bag in around 14 seconds. A slightly rigid structure makes the bag easy to position between the load in the first place.
The quick answer
For everyday container work, an AAR Level 0–2 D-Connect bag sized to fill your void snugly is the right call — the 900 × 1200mm and 900 × 2100mm cover most jobs, with the boxed 100-pack for volume users. Step up to Levels 3–5 for heavy coils and dense freight, and pair the bags with a D-Connect inflator for fast loading. Trade accounts get tiered pricing — and for heavy cargo or bulk supply, email sales@nzpackaging.nz with your void sizes and cargo type and we'll recommend the right bag and level.
Frequently asked questions
How fast can I inflate a dunnage bag?
With the D-Connect inflator, a standard bag inflates in around 14 seconds — significantly faster than older systems, which saves real time across a container.
What AAR level do I need?
Levels 0–2 for filling voids between general cargo; Levels 3–5 for heavy items like steel or paper coils. Email us your cargo details and we'll confirm.
Are dunnage bags recyclable?
Yes — Cordstrap D-Connect bags are made from 100% recyclable materials and are easily and safely removed at the end of the journey.
Can I reuse them?
They can be reused if undamaged and correctly deflated, but many shippers treat them as single-use on high-value loads for guaranteed performance.
