Woodbridge Antiques has dated this piece to the 1940s.
The silver maker's mark is also visible for the silver maker: William Adams Ltd

A super item, fabulous as a gift for any occasion, coming of age, retirement, new baby!
Condition: This flask is fabulous great condition.
Hallmarks: Birmingham 1948 by William Adams
Measurements:
Height: (From base to top of lid): 13.2cm Width: 8 cm Depth: 2.9 cm
Weight: 160 grams (heavy gauge).
l
Weights and measurements are approximate.
NJL33838
Woodbridge Antiques has dated this piece to the 1940s.
Specialists in quality antique silver, fine jewellery & accessories
You can view the stock and full dealer information on the Woodbridge Antiques Profile Page