Uline S-21037 Equivalent: 28 x 4 x 4" Long Boxes (bundle)
Model-to-size mapping verified against Uline’s published catalog listings on July 31, 2026; the Packrift price below is our live catalog price.
Uline model S-21037 is a 28 x 4 x 4" long box per Uline’s published listings. The Packrift exact-size equivalent — same length × width × height, same grade class — is 28x4x4" ECT-32 Kraft Corrugated Boxes - Long Item Shipping, 25-Bundle, priced at $44.64 per bundle today.
| Size | Grade class | Pack | Price today | Per box | |
|---|---|---|---|---|---|
| Uline S-21037 | 28 x 4 x 4" | Long Box | see your invoice | see your invoice | — |
| Packrift equivalent | 28 x 4 x 4" | Long Box | — | $44.64 | — |
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Frequently asked questions
Is this the same box as Uline S-21037?
It matches S-21037’s published dimensions (28 x 4 x 4") in the same grade class, so it packs and stacks the same. It is not manufactured by or affiliated with Uline — when replacing a certified spec, match the certificate stamp printed on the box.
What if my Uline model isn’t listed here?
The cross-reference currently covers 634 verified models across boxes and mailers. Enter yours in the lookup tool, or request a quote with the model number and we’ll match it by spec.
Uline is a registered trademark of Uline, Inc. Packrift is not affiliated with Uline; model numbers are referenced for size-compatibility comparison only.