What is this?

[NRG]

As you will probably recall I have a strong interest (one among many!) of the women’s roles during both world wars and I stumbled across the following photo of one of the 200 ATS’s posted to France in 1940. But I’m at a loss to know what the item (ringed in red) is that she carries on her left hip seemingly hung from a strap over her right shoulder? Any ideas?

 

[PropBlast]

First thing I thought is that it might be a gas mask cannister but then why would you have two of them strapped together? Looks metal to me and a thin wire carrying handle.

 

[arj]

How about a couple of thermos flasks?

 

[Blind Pew]

Whatever it is, it's definitely slung around the shoulder on a strap, which leads me to think it's something needed close by, for immediate use (clean answers only!).
I can only suggest it's a fire extinguisher. What appears to be some kind of mechanism on the top of it certainly suggests so.
If you know what role she may have performed (again, clean answers only!) it may give us a clue...

 

[valiant]

its one if these, with the seam facing outwards.....

 

[Bundook]

Valiant is right. She is carrying the Bottle, Water, Enameled, Mk VI in the Carrier, Waterbottle, Other Services. In leather. It was meant to be part of the '03 pattern mounted set but was never used. After 1942 the straps were in webbing and the nomenclature of the leather set was changed to Carrier, Waterbottle, Home Guard Pattern.

[Edit: I should also maybe add that she apparently has the bottle twisted around in the carrier so the dark "seam" is one of the vertical straps - as shown at the sides in Valiant's picture. Why she'd do this I can't fathom unless it's something to do with the way the shoulder strap lies.]

 

[NRG]

Thank you! Mystery solved. It really is one of those things that if I had modelled it like that someone would have said it was a mistake. Project added to the list.