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Corrugate Resource

How to choose a suitable box

Let’s start by looking at the two most common corrugated container options.

Single wall boxes are considered light to medium duty and are used in retail because they are affordable and provide ample support for most products. Whitebird offers a large selection of stock single wall cartons in 32C ECT which is the most common grade used for general purpose packaging which can support 30-65lbs depending how you are shipping them. We also offer in stock 44 ECT single wall cartons which would be considered medium to heavy duty.

Double wall corrugated boxes are stronger and more durable than single wall boxes. They have an extra layer of liner board and corrugated material, providing added strength and capacity to carry heavier items. These boxes are great for shipping delicate or fragile items as they offer increased protection. Whitebird offers a selection of in stock double wall cartons.

There are two common tests used to evaluate the strength of corrugated boxes: the Edge Crush Test (ECT) and the Mullen Test.

The ECT Test assesses the top-to-bottom compression strength of the box board. This test considers both the box compression strength (BCT) and stacking strength. If your customer wants to know the maximum weight the box can hold, the ECT is typically used.

On the other hand, the Mullen Test measures the bursting strength of the corrugated linerboard and is measured in psi. Customers often opt for the Mullen Test when they are concerned about heavier contents potentially causing the linerboard to burst.

Select an appropriate box strength based on the items you are shipping. The weight limits specified on the Box Maker's Certificate (located on the bottom flap of most boxes) are designed for freight shipments on pallets, rather than for shipments through small parcel carriers. By adhering to these guidelines, you can ensure that your package possesses the necessary strength to offer ample protection. Consult the chart provided below to find recommendations that will assist you in determining the appropriate dimensions and maximum weight limit for your box.

For more information, call our friendly sales staff at 1-800-263-2128

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