I checked my two 49 pound bags and headed for the metal detectors. "What is in here?" the TSA lady asked.
"Oh, you're probably looking at the variable transformer. It is very heavy."
She turned down my offer to help carry the bag to the inspection table - protocol I suppose. "What is this again?"
"A variable transformer, like the AC adapters you plug into the wall, only bigger, and with a knob."
"You wouldn't use something like this in the home, would you?"
"You could, but mostly they are used in more industrial settings for testing electronic equipment and any other time you need fine control over voltage."
"So this thing is high voltage?"
"Only if you plug it into a high voltage source, like that socket over there."
Once I told her that guitarists sometimes use them to adjust the tone of old electric guitar amps, she finally warmed up and decided to let me on my way. Maybe she is a music lover.