Canvas Pouch ID Help - Light 1 G&S 6/43 57 IN

I have several pouches that I got at a garage a few months back and have googled till my fingers have bled with no luck identifying them. Can anyone help?

Two of them are identical but with slightly different markings. They are both marked on the strap and under the lid. One is marked, " LIGHT 1 G&S 6/43. 57 IN". The other is marked, " 57-IN LIGHT 11 H&S 3/43 I.W."

They measure approximately 11" x 5 1/2" x 4 1/2"
I'm guessing they were made in 1943 and are from the US or UK because of the English text.
Can anyone ID them for me? Thanks in advance.Attachment 75404Attachment 75403Attachment 75405Attachment 75406

British P44 light weight respirator pouch.

Agreed, gas mask bag in common parlance.

Third time lucky: it's a haversack for the British 'Respirator, Anti-Gas, Light' that was introduced in 1943. That type of haversack saw use up until the 1970's. Later ones were made in a darker olive green colour. There's also a scarcer 'jungle' version made of different materials.

There are some here locally that would insist that it's a "Bag, holdall, fishing lures and stuff"...

Thanks! I really appreciate all your help.