In Stock SKU: MLR1294K

12x9x4" Kraft ECT-32-B Corrugated Mailers - Crush-Resistant, Bundle of 50

Lightweight 12x9x4" kraft corrugated mailers with ECT-32-B crush-resistant construction ship flat and fold in seconds, no tape, glue, or staples required. Double-wall protection on front and sides. Bundle of 50 boxes saves space and reduces freight costs.

$86.55 / BUNDLE (50 PER BUNDLE)
Order timing and delivery options show at checkout
UPS Eligible — Ground & Freight
Confirm this specSKU MLR1294K

12 x 9 x 4 kraft corrugated mailers, sold as 50/bundle. Commonly used for documents, catalogs, samples, and flat pack shipments.

Size
12 x 9 x 4 in
Material
ECT-32-B Corrugated
Color
Kraft
Sold as
BUNDLE (50 PER BUNDLE)
Freight class
125
Material
ECT-32-B Corrugated Kraft
Dimensions
12" L x 9" W x 4" H
Assembly Method
One-Piece Fold-Together (No Tape/Glue/Staples Required)
Good fit for

Ideal for fulfillment directors and warehouse managers shipping small, high-value items that require reliable protection without assembly overhead. These 12 x 9 x 4" kraft mailers deliver double-wall crush resistance in a lightweight, one-piece design that reduces labor costs and postage expenses while maintaining professional presentation.

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Confirm usable inside dimensions, closure type, color, and pack quantity.

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Best For

Ideal for fulfillment directors and warehouse managers shipping small, high-value items that require reliable protection without assembly overhead. These 12 x 9 x 4" kraft mailers deliver double-wall crush resistance in a lightweight, one-piece design that reduces labor costs and postage expenses while maintaining professional presentation.

How to Choose the Right Packaging

Built from ECT-32-B corrugated kraft, these mailers provide crush resistance with dual-wall protection on front and sides. The one-piece fold-together design eliminates taping, gluing, and stapling, reducing packing labor by up to 60% while flat-storage capabilities optimize warehouse space efficiency and freight density for high-volume operations.

Specs at a Glance

MaterialECT-32-B Corrugated Kraft
Dimensions12" L x 9" W x 4" H
Assembly MethodOne-Piece Fold-Together (No Tape/Glue/Staples Required)
Bundle Quantity50 Mailers Per Bundle
RecyclableYes
Common Use Cases
  • E-commerce order fulfillment for tools, hardware, and small parts Shipping fragile items including glassware, electronics, and delicate merchandise High-volume direct-to-consumer packaging with postage optimization Secondary protective packaging for retail and wholesale distribution Temperature-sensitive product shipments requiring lightweight, stackable protection
What You'll Receive
  • 50 pre-scored, one-piece kraft corrugated mailers (12 x 9 x 4") Ready-to-fold design, no additional assembly materials needed
Shipping & Packaging

All mailers ship and store completely flat, maximizing warehouse space utilization and reducing inbound freight costs. Bundles of 50 stack efficiently for bulk inventory management and rapid order fulfillment.

Frequently Bought Together

Bundle & Save 5%

Frequently Asked Questions

ECT (Edge Crush Test) 32-B represents 32 pounds of crush resistance per linear inch of corrugated edge. This mid-range rating provides excellent protection for small-to-medium items while maintaining lightweight properties that reduce per-unit postage costs, critical for high-volume B2B fulfillment centers managing cost-per-shipment metrics.

Operators pack, fold, and close each mailer in approximately 8-12 seconds with zero additional materials. Traditional taped boxes require 20-30 seconds per unit. At 500+ shipments daily, this design eliminates 2+ labor hours per shift while reducing tape and supplies inventory.

Yes. The double-wall construction on front and sides, combined with ECT-32-B kraft rating, provides crush resistance suitable for glassware, small electronics, and tools. Pair with internal cushioning (bubble wrap, kraft paper) for optimal fragile-item protection in standard shipping environments.

Flat storage reduces warehouse footprint by 85% compared to pre-assembled boxes, freeing high-value shelf space for inventory. A pallet of flat mailers (10,000 units) occupies roughly 12 cubic feet versus 200+ cubic feet for equivalent assembled inventory, delivering measurable ROI on warehouse optimization.

Technical Specifications

MaterialECT-32-B Corrugated Kraft
Dimensions12" L x 9" W x 4" H
Assembly MethodOne-Piece Fold-Together (No Tape/Glue/Staples Required)
Bundle Quantity50 Mailers Per Bundle
RecyclableYes
Color Kraft
Strength / Material ECT-32-B Corrugated
Dimensions (Internal) 12"" × 9"" × 4"" (L × W × H)

Product Downloads

Shipping Information

Outer Carton Dimensions

31.0" × 29.5" × 5.75" (L × W × D)

Unit of Measure

BUNDLE

Qty Per Shipping Unit

50 PER BUNDLE

LTL Freight Class

Class 125

Carrier Eligibility

UPS Ground & Freight Eligible

TRUST & RELIABILITY

Product Support

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Secure checkout LTL freight available on case/skid orders