6x4x4 Kraft Corrugated Mailers ECT-32-B Crush Resistant, Bundle of 50

$43.00
/ bundle of 50$0.86 per mailer
Request bulk pricing
Ships from the nearest of 5 US warehouses · freight calculated at checkout
30-day returns on stock items · Return policy
Inside dimensions
6" × 4" × 4"
Board / material
ECT-32-B Corrugated
Color
Kraft
Freight class
Class 125
Specifications
| Inside dimensions | 6" × 4" × 4" (L × W × H) |
|---|---|
| Board / material | ECT-32-B Corrugated |
| Color | Kraft |
| Sold as | Bundle of 50 |
| Order in multiples of | 50 |
| Bundle weight | 8.58 lb |
| Outer carton (shipping) | 21.0 × 14.75 × 5.75 in |
| LTL freight class | Class 125 |
| GTIN | 848109008622 |
| SKU | M644K |
About this item
SKU M644K — 6" × 4" × 4", ECT-32-B Corrugated, Kraft. Sold as a bundle of 50, shipped from US warehouses.
Common questions
What does ECT-32-B mean, and why does it matter?
ECT (Edge Crush Test) 32-B indicates the mailer can withstand 32 pounds of crush force per linear inch. This rating ensures your shipments stay protected through multi-handling, stacking, and freight consolidation, critical for high-volume fulfillment operations where boxes endure repeated compression.
How much space and shipping cost do I save with flat mailers?
Flat-pack mailers reduce inbound freight volume by approximately 85-90% compared to pre-assembled boxes. When you store and handle 50 units in a compact flat bundle versus 50 assembled cartons, you free up 3-5 cubic feet of warehouse space per SKU and cut receiving labor by 40-60%.
Do these mailers work without tape or additional materials?
Yes. The one-piece fold-and-tuck design locks automatically when folded, no tape, glue, staples, or adhesives required. This accelerates pack-and-ship cycles, eliminates supply chain dependencies on tape inventory, and reduces per-unit packing costs by $0.05-$0.12.
What products ship best in a 6 x 4 x 4 mailer?
Ideal for tools, small hardware, glassware, lightweight electronics, cosmetics, books, and bundled items weighing under 10 pounds. The double-wall crush-resistant design protects fragile goods while the lightweight kraft construction minimizes outbound postage for USPS Priority Mail, UPS Ground, and FedEx SmartPost.
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.



