51 ECT Boxes: Double-Wall Heavy-Duty (8 In-Stock Options)
51 ECT is a double-wall corrugated grade — an edge crush rating of 51 lb/inch, roughly the 350 lb burst class — used for dense, stacked, and haz-mat loads. Packrift stocks 8 ECT-51 boxes today from $40.06 per bundle, including UN-certified haz-mat cartons, shipped from 5 US warehouses with live freight at checkout.
| Box | Class | Price today |
|---|---|---|
| 30x17x17 Double Wall ECT-51 Corrugated Boxes - Heavy-Duty Shipping, Bundle of 5 | Double-wall heavy duty | $40.06 |
| 36x22x22 Double Wall ECT-51 Corrugated Boxes - Heavy-Duty Shipping, Bundle of 5 | Double-wall heavy duty | $70.66 |
| 12 1/8x12 1/8x13 9/16 ECT-51 Haz Mat Boxes - UN Certified, Bundle of 10 | UN-certified haz-mat | $92.72 |
| 58x41x45" ECT-51 Double Wall Corrugated Box - Heavy-Duty Shipping Carton | Double-wall heavy duty | $122.76 |
| 46x8x30 ECT-51 Double Wall TV Box - Full Overlap Kraft Carton, Bundle of 5 | Double-wall heavy duty | $130.63 |
| 14.25x14.25x7.625 ECT-51 Haz Mat Boxes - 4-Gallon Capacity, Bundle of 10 | UN-certified haz-mat | $131.42 |
| 6 3/4 x 4 5/16 x 10 3/8 ECT-51 Hazmat Paint Can Boxes - Bundle of 20 | Double-wall heavy duty | $139.45 |
| 9x6 11/16x10 1/4 ECT-51 Double Wall Hazmat Boxes - 2 Gallon F-Style, Bundle of 20 | Double-wall heavy duty | $224.22 |
When 51 ECT is the right call
Choose ECT-51 when a load is heavy and concentrated — machinery parts, dense hardware, TV-size flat panels — or when boxes ride double-stacked on pallets and the bottom tier carries the pile. The UN-certified haz-mat versions add the certification lab work for regulated contents. For heavy-but-ordinary shipping, ECT-48 double-wall (nearly 200 stocked options) usually does the job for less; the strength ladder is on the ECT-44 size chart and the ECT-to-Mullen conversion table.
See live price & freightRequest a bulk quote
Frequently asked questions
What does 51 ECT mean on a box?
ECT-51 is a double-wall corrugated grade with an edge crush test value of 51 lb per inch — roughly the 350 lb burst-test class. It is built for dense, heavy, or stacked loads where a standard ECT-32 single-wall box would bulge or crush.
51 ECT vs 48 ECT — which do I need?
Both are double-wall. ECT-48 (about the 275 lb class) covers most heavy shipping; step up to ECT-51 when contents are very dense, palletized and double-stacked, or when a haz-mat spec calls for a UN-certified pack. If your spec sheet uses burst ratings, see the ECT-to-Mullen conversion chart.
Grade guidance is general; confirm certification requirements for regulated shipments on the product page before ordering.