An Elctroplated Britannia Metal Flask by James Dixon & Sons of Sheffield
The small glass flask is covered with leather to the top half with a removable cup to protect the bottom half. The cap unscrews and is completely removable as opposed to working on a half turn bayonet fitting, like most flasks.
The underside of the cup is marked JD&S with the trumpet in banner logo for James Dixon & Sons who were prolific makers of flasks. Its also has the size 1/8 pints, the design dumber 528A, Made In England and EPBM.
The flask is by a good maker and a great small size. Early 20th Century.