Originally Posted by Matt Thomas
Can you describe the difference between your industrial plates and your light-industrial plates?
Industrial plates use a harder rubber, the insert fits more snug to the bar, made with more accuracy (less deviation in sizing of insert), and also undergoes a multiple step process when melted to the rubber so that it holds better.
We use a harder rubber so that the plates have less waffle when a bar is dropped on them. That is a common reason why many of them break... when they fold, it's putting a lot of pressure on the area around the insert. The harder rubber REALLY becomes an advantage when you're talking about thinner plates: 10s and 15s. On the thicker bumpers, they're not going to waffle anyway, but you still get inserts that fit more snug and the multiple step process to hold to the rubber better.
If I were buying myself and trying to get best value, I'd get 10s and 15s in industrial and 25, 35, 45 in light-industrial.