Rusty wrote:
I'm pretty sure the kitchen mixer tap I got from Texas (as it then was) 10
yrs ago only has a single tube in the nozzle. It rotates through 360 deg.
without stopping. The 1960's mixer it replaced, which at one time were very
common, did have did have two tubes in the nozzle, but wouldn't rotate all
the way round. I can't think of a practical way to manufacture a 360
rotate with two tubes.

The two tubes are concentric, with the cold on the outside so the tap
spout doesn't get too hot to touch.

Owain