3x3x18 Kraft Square Mailing Tubes 25-Pack M3318K
$40.87
/ bundle of 25$1.63 per tube
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Secure checkout
| Quantity (bundle) | Item-subtotal discount |
|---|---|
| 1–2 | Base item price |
| 3–5 | 3% off qualifying item subtotal |
| 6+ | 5% off qualifying item subtotal |
| Pallet or repeat orders | Get a delivered quote |
Shipping & deliveryCheck cost to your ZIP code
Shipping & returns details
Ships from U.S. warehouses. 30-day returns on unopened stock items.
Shipping cost and timing depend on the product, quantity and destination. Parcel or freight service is used as appropriate. Shipping discounts apply only to qualifying orders and rates.
Standard delivery is to street addresses in the contiguous U.S. Eligible returns must be unused and in original packaging; return shipping may apply.
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Inside dimensions
3" × 3" × 18"
Board / material
ECT-32-B Corrugated
Color
Kraft
Freight class
Class 125
From our customers
“The packaging is sturdy, well-made, and looks professional. We’re really pleased with the quality.”
“They helped us choose the right packaging for our products and made ordering easy.”
“Ordering was easy, everything arrived as described, and we’ll definitely order again.”
Questions before you order?Talk to us
Specifications
| Inside dimensions | 3" × 3" × 18" (L × W × H) |
|---|---|
| Board / material | ECT-32-B Corrugated |
| Color | Kraft |
| Sold as | Bundle of 25 |
| Physical units per order increment | 25 (one bundle) |
| Bundle weight | 3.58 lb |
| Outer carton (shipping) | 28.0 × 17.25 × 3.0 in |
| LTL freight class | Class 125 |
| SKU | M3318K |
About this item
SKU M3318K — 3" × 3" × 18", ECT-32-B Corrugated, Kraft. Sold as a bundle of 25, shipped from US warehouses.
3x3x18" kraft mailers in paper stock, packed 25 per pack (SKU M3318K); this is a second listing of the same BOX case stock at the same price.
Sized for shipping and fulfillment work; closes with tape or the built-in flap. Order by the pack of 25.
Common questions
Why choose square tubes over round mailing tubes?
Square tubes eliminate rolling during transit, reducing product damage and customer complaints. They stack efficiently in trucks and pallets, lowering shipping weight and costs. The flat design also maximizes shelf space in warehouses compared to bulky round alternatives.
Are these tubes USPS/UPS/FedEx compliant?
Yes. ECT-32-B kraft corrugated meets all major carrier specifications for dimensional weight, edge crush strength, and burst resistance, ensuring acceptance without additional fees or delays.
Do I need tape or glue to assemble these tubes?
No. These one-piece tubes fold together in 10-15 seconds without any adhesives or tools. The interlocking design ensures secure assembly for immediate packing and shipping.
What products fit safely in a 3x3x18" tube?
Ideal for posters, rolled artwork, blueprints, technical documents, fabric samples, rolled signage, and cylindrical products under 3" diameter. Maximum recommended contents weight is 5 lbs for optimal carrier compliance.
Order support
Questions on specs or freight?
Send the SKU, quantity, and delivery ZIP and we will confirm specs, availability, and freight before you order.