Look at "K" on the "Chemical laboratory apparatus" list.
That means that if you have an electrical transformer, the police have probable cause to bust you for manufacturing drugs. (The charge may not stick, but they can bust you on it.)
You have to have a permit from the State of Texas to buy a transformer.
And look at the list of "chemical precursors": "Pseudoephedrine". That means you need a special license to buy Sudafed.
But back to the thing about "transformer": do you have any devices which are powered via a "wall wart"? Guess what? That's a transformer!
Own a UPS for your computer? Guess what's in there?
I probably have about 20 transformers, not including the ones in my pile of electronics parts and tools.