What is this coil?

This coil is on the main water line near the water meter. Can someone tell me what it is?
Thanks

Used parts from an old still???

My guess would be a homemade air hammer arrestor.

Thank you! Boy you are quick.

Its a warm up coil allows the water in the winter to warm up to room temp before entering the water heater unless someone is using a large amount of water then you get what you get

Wow, it is hard to believe there would even be a gallon in that coil, eh? :shock:

Heck Larry I have no clue I was just messing with those two guys that was making a wild A** guess so I thought I would also sounded good did it not;-)

Feeder for the icemaker??? (It’s a thin copper tube.)

Supply line for a dental chair?

The plumber forgot to bring his tubing cutter that day.

Gotcha…

or stiffed 'em & didn’t install the drain line
either way a useless waste

What is it connected to?

It was connected to a short nipple sticking out from the piping near the Water Main. Connected right next to it was a twin of this, so the homemade water arrester theory by Roy seems to be spot on.