Wiring – the meaning of the term “trade size”


While shopping for electrical parts for the next project, I keep seeing the term Trade Size. What exactly is this a measure of?

Best Answer

It simply means what the item is referred to in size, .vs. what any actual dimension may be. "Nominal" size means the same thing.

So, 1/2" EMT (for example) is 0.706" on the outside and 0.622" on the inside, and 0.500" nowhere.