Woodbridge Antiques has dated this piece to the 1940s.
There are also maker's marks visible for DNH&S.

A good heavy gauge napkin ring. Feels nice and solid
Condition: The napkin ring is in great used condition. No visible dents to the silver.
Hallmarks: Sheffield 1944
Measurements:
Height: 3.2 cm approx
Diameter: 4.5 cm approx
Weight: 27 grams approx.
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