This is a grey-coloured glass water jug made by Sowerbys' Glass in an Art Deco style. It's from their pattern 2550 Water Set, made in clear glass and also in four colours: amber, blue, green and this grey colour, known as flint. Some colours are harder to find, which affects the price, but they're all sturdy, usable jugs.
There's no mark, but it was made by Sowerbys' Ellison Glass Works Limited of Gateshead in the 1950s (see the catalogue reproduction at 20th Century Glass).
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