All corrougated boxes listed are 32ECT.
Edge Crush Test (ECT) measures the stacking strength of corrugated cardboard boxes or fiberboard. Determining a finished box's compression strength is defined by the amount of force that is needed to crush cardboard by standing it on its edge.
This test is also measured in lbs per square inch. For example, a box with an ect 32 lbs per square inch indicates that the board, standing on edge, can withstand a force of 32 lbs per square inch before crushing.
Think about the movement of your boxes during transportation. At some point during a move it is likely your boxes will be stacked on a pallet, in a container or in the back of a truck. Yes, stacking is the key concept behind ect. Know the strength of your corrugated cardboard boxes before stacking.