This one has me stumped

To-day’s inspection was a 40 year old house with aluminum wiring. I did the usual with the aluminum.

One junction box in a crawl space adjacent to the attached garage had a 1/4 inch aluminum tube. The tube exited the foundation wall and could not be found anywhere. This tube appeared to be carrying voltage. I have no idea and would appreciate any comments.

looks like a old pipe heater.

pretty thin for conductors that power heat. (no)?

Any chance there was a doorbell transformer plugged into that porcelain plate at one time?

Although it looks to have been replaced by plastic.

Looks like an old BX Clamp.