corrugated box

Box Maker’s Certificate: How to Read Your Box Stamp

Photo of author

Packaura

/ November 13, 2026

Flip over almost any corrugated shipping box and you’ll find a round or oval stamp near the bottom seam, packed with abbreviations like “ECT 32” or “Mullen Test 200 lbs.” That’s the box maker’s certificate (sometimes called a box manufacturer’s certificate, or BMC), and it’s

Read more